Definition of stack in US English:



  • 1A pile of objects, typically one that is neatly arranged.

    ‘a stack of boxes’
    • ‘Sheriff Vasey was sat at his desk, lines of worry incised into his face as he tried to ignore the storm and concentrate on the stack of paperwork piled up in front of him.’
    • ‘I got out my small stack of exams from my summer class and, looking up once in a while to watch the people pass by, I graded question 1.’
    • ‘Her bed had a whole stack of clothing piled up and it was getting higher.’
    • ‘Vincent moved silently into a deep shadow on the other side of the room, going behind a stack of crates piled in the middle of the floor.’
    • ‘She greeted her brother, as he finally walked over to the car, a stack of books piled up to his chin.’
    • ‘A stack of kindling was piled on the floor nearby and he tossed some in, quickly lighting a fire.’
    • ‘‘Come in,’ she called absently, slaving over a stack of papers neatly arranged on her desk.’
    • ‘‘These should be your size,’ she handed him a stack of neatly folded clothes.’
    • ‘Most amazing of all, there was a stack of gifts piled on the chair in the corner.’
    • ‘I climbed up a stack of old crates arranged haphazardly behind the warehouse.’
    • ‘At other times, her mother lay in bed for days, not bothering to get dressed, reading from a stack of books piled on her bedside table.’
    • ‘He grabbed a nearby stack of bandages and piled on one after the other until he felt there was enough to soak up the blood.’
    • ‘It was then that her hand slid across what sounded like a stack of neatly clumped paper.’
    • ‘The man heaved as he piled the stack of six books onto Roy's already dusty lap.’
    • ‘Deia's stepmom emerged underneath the staircase with a stack of neatly folded clothes and shot Vaius a look of dislike and poisonous curiosity.’
    • ‘Do you have a stack of books piled beside your bed that you really are going to read?’
    • ‘Neither the pile of work related e-mails in my inbox nor the stack of paperwork on my desk can put a dent in my enthusiasm.’
    • ‘Groaning and pushing myself up, I shuffled over to my bathroom, almost tripping on a stack of books piled near my bathroom door.’
    • ‘Emanuelle frowned as she traced her fingers down the stack of folders neatly piled inside.’
    • ‘She opened her mouth to say something, but Valora Adora bustled back into the room with a small stack of neatly folded colorful clothing.’
    heap, pile, mound, mountain, pyramid, mass, store, stockpile, hoard, load, tower, drift, clamp, hack
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    1. 1.1a stack of/stacks ofinformal A large quantity of something.
      ‘there's stacks of work for me now’
      • ‘Plus, loggers get to eat stacks of pancakes every day.’
      • ‘There are stacks of people who have e-mailed me or commented over the last year or so who I would love to meet in the flesh.’
      • ‘Kearsley and Horwich piled up a stack of runs in an entertaining draw.’
      • ‘The next type of beggars were some people walking around with stacks of CDs in their hands on the Walk of Fame.’
      • ‘Before it, a desk with stacks of waiting paperwork held vigil, its dark wood surface holding old ink stains.’
      • ‘There will be some people who have stacks of confidence and some who have none.’
      • ‘Yet a growing stack of academic research this year suggests that playing Doom or Half-Life can sharpen your physical reactions and improve your social life.’
      • ‘The first track opens with what might be a guitar solo filtered through massive stacks of electronics as insect-like squeals pour out of the speakers.’
      • ‘Stalin closed the show for the three nights and sang four of his classics from his stack of hits.’
      • ‘It seems that absence does make the heart grow fonder for on our return, what do we find but stacks of great emails from you.’
      • ‘I still have plenty to do, and a stack of emails that are waiting for replies, but they will have to wait until later in the week.’
      a great deal, a lot, a great amount, a large amount, a large quantity, quantities, plenty, abundance, superabundance, plethora, cornucopia, a wealth, profusion, a mountain, reams
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    2. 1.2 A rectangular or cylindrical pile of hay or straw or of grain in sheaf.
      • ‘I finished with the dirty hay and began piling clean hay from a stack on the far wall, leaving the wheelbarrow for another time.’
      • ‘We used to build stacks mainly in the stackyard by the farm buildings but occasionally we built some in the field.’
      • ‘From another hole came the straw that was again piled into a stack.’
      • ‘Our only pickup truck was used to operate the overshot stacker that piled the hay into stacks.’
      haystack, rick, hayrick, stook, mow, haymow, barleymow
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    3. 1.3 A vertical arrangement of stereo or guitar amplification equipment.
      • ‘The drums were coming through this huge amplifier stack and it was louder than onstage.’
      • ‘The hearing of both Ozzy Osbourne and The Who guitarist Peter Townshend was damaged by prolonged exposure to the high wattage blare from stacks of amplifiers.’
      • ‘Top-end CPUs do note readily make for a slimline, quiet-running unit to sit within a hi-fi stack.’
      • ‘A new venue meant yet another sound-check to make sure that the reassembled stacks of amplifiers and speakers had been matched to the concert hall's acoustics.’
    4. 1.4 A number of aircraft flying in circles at different altitudes around the same point while waiting for permission to land at an airport.
      • ‘They thought the stacks of green aircraft belonged to Army fliers.’
      • ‘Being in the dominant position, on top of the stack in the start circle, is a strong tactical advantage.’
      • ‘Beaten-up airplanes will always be at the bottom of the stack.’
      • ‘We lost our situational awareness of the other aircraft in the overhead stack.’
      • ‘The 10 aircraft made an impressive sight as they hovered in a stack above HMAS Albatross.’
    5. 1.5 A pyramidal group of rifles.
      • ‘I recall M/Sgt Widner, a high school ROTC instructor, demonstrating that this arrangement, when properly done on a grass parade field, was strong enough that a soldier could stand (one legged) on the stack.’
      • ‘Coronach if you get 9 more rifles you could set up a table in your living room where each leg is a rifle stack.’
      • ‘This won't be as sturdy as a stack made by three M1s or three '03s.’
    6. 1.6the stacks Units of shelving in part of a library, used to store books compactly.
      • ‘Neither outside nor inside the library did I see any sign of where one might deposit one's weapon before browsing in the stacks or settling into the periodicals room.’
      • ‘Nearly every day I'm at the library, searching the stacks.’
      • ‘This is the version that will go into print and be found in the stacks at the library.’
      • ‘The librarian sped away along the stacks of books.’
      • ‘Books will be fetched by Library staff from the stacks downstairs, where the collection will be housed in suitable conditions of security, temperature and humidity.’
      • ‘For today much, perhaps most, of a student's search for information has moved out of the stacks and into dorm rooms and studies, via the Internet.’
      • ‘Perhaps it took that long to declare the book lost from the stacks of the Geneva Public Library District.’
      • ‘I used to go to UCSD's Central Library and browse the stacks, especially the economics section.’
      • ‘Some of them were friendly and even allowed the use of dollies to transport the books from the stacks to the check-out desk.’
      • ‘They're the smell of yellowed book pages in the stacks of an abandoned library.’
      • ‘People will want to live in a coffee shop, talking to people about books, not in the stacks at the library or the warehouse at Amazon.’
      • ‘Sneak the book back into the stacks and tell them they screwed up because you returned it long ago, or else hold onto it until the next amnesty period.’
    7. 1.7Computing A set of storage locations which store data in such a way that the most recently stored item is the first to be retrieved.
      • ‘Within the protocol stack, SSL / TLS is situated underneath the application layer.’
      • ‘By implementing VI, applications can communicate with each other directly, bypassing the operating system and protocol stacks.’
      • ‘Execshield also randomizes the memory address of a program stack to make it harder for malicious code to know where to gain entry into the program.’
      • ‘The gateway holds the hardware interfaces and software protocol stacks to get all the various technologies talking nicely to one another.’
      • ‘The search engines are virtual librarians who take your order and retrieve documents from the stacks in less time than it takes your browser to load the next page.’
  • 2A chimney, especially one on a factory, or a vertical exhaust pipe on a vehicle.

    • ‘There is no release of gases into the atmosphere except through the exhaust stack.’
    • ‘A downdraft over the stack is causing the sewer gas to be more noticeable.’
    • ‘My brother and I were flying one day when the engine suddenly lost 60 percent of its power and heavy black smoke started pouring from the exhaust stacks.’
    • ‘The noise from the multiple exhaust stacks is spectacular and very satisfying.’
    • ‘The atrium lobby acts as a stack, with horizontal vents at floor and ceiling.’
    • ‘Because the fare burns quickly at a high temperature, it also burns cleanly, with virtually no emissions up the stack.’
    • ‘He hides on his roof behind a stack of chimneys until the people finally disperse.’
    • ‘Between the stack and the vertical wall there are many large holes or caves full of groupers.’
    • ‘Exhaust stacks and courtyards increase access to air movement and daylight.’
    • ‘We would now suggest it is best if we totally by-pass the existing outlets and connect our own outlets directly into the pipe stacks.’
    • ‘For night flying, engineers added special flame-suppressing exhaust stacks to it to prevent night blindness in crew members.’
    • ‘One exhaust stack will be virtually right next door to the Gabba.’
    • ‘Also effective was a tall stack exhaust port which expels the fumes above the boat where they can more quickly dissipate in the air.’
    • ‘Police can drown the engine of a bigger ship by firing a water cannon into its exhaust stacks.’
    • ‘Of course the plating process is not the only finishing process these truck exhaust stacks go through.’
    • ‘She blew a series of smoke rings out, because she knew that it amused me, stretching her head into the air like her neck was a stack and her lips the chimney rim.’
    • ‘Unfortunately, toxic metals escape out the incinerator's smoke stack into the atmosphere.’
    • ‘Cameron hesitated as he took in the roof, his vision blocked by other staircase entries, chimneys and vent stacks.’
    • ‘In addition, windows surrounding the cab increase visibility, and exhaust stacks are in line with the cab post, lending to a quieter engine.’
    • ‘On we drove past the CJ Rance timber mill where life stood still on this holiday long weekend, save for blue smoke seeping from wood-curing stacks.’
    chimney, factory chimney, chimney stack, smokestack, funnel, exhaust pipe
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    1. 2.1British A column of rock standing in the sea, remaining after erosion of cliffs.
      • ‘Looking south you see the 220 ft sea stack, sentinel of the beach, Am Buachaille - the herdsman - which was first climbed in 1967.’
      • ‘The climbing partner of a man who fell to his death in Orkney last week has told The Orcadian how a last-minute decision to tackle a 12-metre stack ended in tragedy.’
      • ‘The climb to the top of the 450 ft sea stack was to raise money and awareness of the plight facing patients with kidney problems.’
      • ‘This remote corner of Washington's Olympic Peninsula is upholstered with deep forests of cedar, spruce and fir looking over rock cliffs, sea stacks and wave-carved caves to the open Pacific Ocean.’
      • ‘The Old Man of Stoer comes into view shortly after this, and you follow the cliff edge round to the right and then down steeply to look over the sea stack.’
      • ‘He, along with Graeme Nicol and the lyric mountain churl Tom Patey (who died in 1970 falling off a sea stack called The Maiden), did the first ascent of Ben Nevis's Zero Gully, then one of the hardest ice climbs in the world, in 1957.’
      • ‘The sandstone cliff ledges and stacks provide suitable nesting and roosting areas for some species, while three of the four main islands in the area are ideal breeding grounds for large gulls.’
      • ‘I finished my pint in the ship's bar and went to the starboard viewing rail to watch the sunlight reflecting off that famous sea stack, the Old Man Of Hoy.’
      • ‘Additional features include a private island - a small sea stack known locally as The Stag - and a 24 square metre self-contained Swiss chalet in the back garden, which features two bedrooms, a living area with kitchenette and a shower room.’
      • ‘The sea stack of Am Buachaille stands to the south end of the bay although it is best viewed from the middle or the northern end.’
      • ‘A team of scientists investigating ruins atop a remote sea stack in the Western Isles this summer have been using a Troylean sling to get to the remains of a medieval castle.’
      • ‘The other arch stands close by - a Cyclopean gateway through a tall and slim sea stack.’
      pillar, column
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[with object]
  • 1Arrange (a number of things) in a pile, typically a neat one.

    ‘the books had been stacked up in three piles’
    ‘she stood up, beginning to stack the plates’
    • ‘Spread the manure thinly outdoors so that fly eggs and larvae can be killed by drying, or stack the manure and cover with black plastic.’
    • ‘Here and there on the curb, other entrepreneurs hack shoe soles out of used tires and stack the soles in neat bundles for resale.’
    • ‘The banker can stack the appropriate number of chips on top of the puck to indicate how many consecutive wins he has.’
    • ‘A desk spanned the width of the room, and there were files folders and CDs stacked in neat piles on the desk, and a computer built into it.’
    • ‘High ceilings provide the clear height to stack a large number of equipment racks and to accommodate overhead services.’
    • ‘Karl finally had five neat piles of photos stacked.’
    • ‘Leafy veggies which are not sold are stacked into vegetating piles which emanate a stink and consequently create health hazards for denizens.’
    • ‘She picked up the dishcloth and started to wipe the plates, stacking them in neat piles of 5.’
    • ‘The Baron was in the Great Hall, counting coins and stacking them in piles.’
    • ‘The wise magician then ordered the young prince to spend the day lugging and stacking a pile of huge logs, menial labor unbefitting royalty.’
    • ‘The books that couldn't fit on the shelves were stacked in neat piles nearby.’
    • ‘More money than even I had seen in my lifetime was stacked in piles around the linoleum floor.’
    • ‘Ian wandered back into the cave and began sorting what was left into packsack-sized piles, stacking them by the mouth of the cave.’
    • ‘We sat at the big table and watched my mum count the coins, stacking it all into neat piles by denomination.’
    • ‘While I rinse plates and stack them in the dishwasher, I decide to call Renee to see what she thinks.’
    • ‘During the day these pillows are stacked in a pile and the room is converted into a place for sitting and eating.’
    • ‘I'd stack hatboxes covered in floral-print paper in a corner.’
    • ‘Inside, the chairs are stacked in three neat piles on the porch.’
    • ‘A series of photograph of two toddlers earnestly stacking a pile of blocks only to knock them back down will be accompanied by this dialogue.’
    • ‘As the men progress to the next tree, a woman gathers up the curved strips of cork and stacks them into a pile.’
    heap, heap up, pile, pile up, make a heap of, make a pile of, make a stack of
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    1. 1.1 Fill or cover (a place or surface) with piles of things, typically neat ones.
      ‘he spent most of the time stacking shelves’
      • ‘Compared to Watkins, Atlantis is a bit grubby and poorly lit and the place is stacked with arcane junk.’
      • ‘Her shelves are stacked with cookbooks and clippings, her drawers filled with gadgets and graters.’
      • ‘The only table that can fit into the tight living room is stacked with books and papers.’
      • ‘The bath is stacked with bottles of shampoo, conditioners and various beauty-enhancing lotions and potions.’
      • ‘His lack of selectivity only stacks the shelves higher.’
      • ‘Every housewife stacking her shelves should be proud to have her tins of beans stamped with a such a badge of high distinction.’
      • ‘Most people would just shrug and go get a job stacking shelves in Tescos.’
      • ‘And, very definitely, I love to let my eyes swerve over those endless rows of covers stacked upon shelves.’
      • ‘Journal pages have to be filled, and library shelves have to be stacked with books.’
      • ‘My bravado from earlier dwindled as he nodded, smiled again, and continued stacking the shelves.’
      • ‘Some of the storage areas are stacked with hundreds of baskets that were soaked in poison years ago because at the time it was the only way to protect them from bug infestation.’
      • ‘This time he stood with his back to them continuing to stack the shelves with more force than necessary.’
      • ‘When I was 15, I got a job stacking shelves in Dunnes Stores.’
      • ‘Cabinets around the room were stacked with china dishes.’
      • ‘Every surface is stacked with knick-knacks; every chair piled with quilts.’
      • ‘As it turns out the ‘poor old man’ picks up the internal trolley used for stacking the shelves and tries to claim the missing £1.’
      • ‘Then one day while I was stacking the shelves, I collapsed.’
      • ‘If you want a knot garden in your own space, stack the central spaces in the middle of your evergreen outline now with as many herbaceous perennials as you can.’
      • ‘The place was stacked with empty boxes and cages to carry them around.’
      • ‘A great shelf which covered that whole wall was stacked with age old books!’
      load, fill, fill up, lade, pack, charge, stuff, cram
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    2. 1.2 Cause (an aircraft) to fly in circles while waiting for permission to land at an airport.
      ‘I hope we aren't stacked for hours over Kennedy’
      • ‘Lines had to be shared with people dialling up, ringing off and basically stacking like planes outside Heathrow airport.’
      • ‘And you can see that the controllers are just stacking them up all along the East Coast here and then sending them around.’
      • ‘The claimant soon became aware of the noise from aircraft stacking over Mayfield.’
  • 2Shuffle or arrange (a deck of cards) dishonestly so as to gain an unfair advantage.

    • ‘Yes, some people are born with the deck stacked against them.’
    • ‘Life is just too hard, impossible even, and the cards have been totally stacked against me for years.’
    • ‘When Bernie falls in love, the chips in his life begin to fall into place, just as cards begin to get stacked against Shelly and his old-school values.’
    • ‘But then again, the deck is completely stacked against him.’
    • ‘She felt like the cards where stacked against her.’
    • ‘The quarterbacks get paid the most money because they must rally the troops in the game's critical moments when the cards are stacked against them.’
    • ‘Or are the cards always stacked in favour of one group?’
    • ‘I believed that Meg and Sarah were in real danger at the beginning; by the second half of the movie, I felt that the cards were stacked so unfavorably against the robbers so as to negate the danger.’
    • ‘But Bremer starts with the cards seemingly stacked against him.’
    • ‘I watch it played on TV all the time, I know when cards were stacked.’
    • ‘Fate was definitely stacking the cards against me.’
    • ‘When he and his team took office on May 20 last year, the cards were already stacked against them.’
    • ‘At three-quarter time the Eagles were still down 8.9 to 12.4, and the cards still seemed stacked Westies' way.’
    • ‘On the face of it, the cards seem stacked against him.’
    • ‘Your focus on ‘yields’ of individual commodities, rather than total output, unfairly stacks the deck by ignoring a large measure of what smaller farms produce.’
    • ‘The winemaker is constantly battling to create a bottle of wine that, from the outset, has the deck stacked against it.’
    • ‘But another source said the cards were not all stacked in Regent's favour, as it needed to close a deal in order to strengthen its pubs portfolio beyond Walkabout bars.’
    • ‘The cards are stacked against detainees in other ways too.’
    • ‘You might think that lawyers acting in a Family Court dispute up against a self-represented litigant might be pleased, after all the cards are stacked in their favour.’
    • ‘The question brings me back to an issue that I promised to address: the possibility that Mitch was stacking the cards a bit when he didn't clarify how his teacher/hero needed to be needed.’
    1. 2.1be stacked against/in favor of Used to refer to a situation which is such that an unfavorable or a favorable outcome is overwhelmingly likely.
      ‘the odds were stacked against Fiji in the World Cup’
      ‘they found the courts stacked in favor of timber interests’
      • ‘Little Maisy and Ruby Jolly have been dubbed the ‘Miracle Twins’ after the odds were stacked against their survival.’
      • ‘Despite all the odds being stacked against them, Mandi and David are determined to be together.’
      • ‘The odds were stacked against them but there was no lack of self-belief from the Tigers, who subjected the Wakefield line to an onslaught.’
      • ‘Frye's turnout surprised San Diego voters partly because, from a practical standpoint, the odds were stacked against her.’
      • ‘The odds were stacked against the 17-year-old Toowoomba student from the start, but he triumphed anyway.’
      • ‘Add in that he was out of action for a couple of months earlier this year with a knee injury and it's clear the odds were stacked against a comeback.’
      • ‘The visitors were short their best two players so the odds were stacked against them before the ball was thrown in.’
      • ‘When you consider how the odds were stacked against us it was a fantastic display and result.’
      • ‘Wolff Reik, cloning expert at the Babraham Institute, Cambridge, said even if the woman became pregnant the odds were stacked against the baby.’
      • ‘While the odds were stacked against them, the trio were able to establish contact with Wellington-based Maritime Radio which relayed their plight to Bay of Plenty Coastguard.’
  • 3no object (in snowboarding) fall over.

    • ‘The group I ride with all got a shock last year when our friend stacked it, came down on his head and spent the next 6 months in hospital.’
    • ‘Then on his very first session on a his brand-new recently arrived real deal snowboard, he stacked it and broke both legs just below the knee, ouch.’


  • stack arms

    • Place a number of rifles with their butts on the ground and the muzzles together.

      • ‘About 2 a. m., after passing through a valley amid darkness which was greatly increased by a dense wood, the troops were allowed to file off, stack arms, and bivouac on a slope, and around a knoll upon which some of our cavalrymen had been stationed on picket duty.’
      • ‘Several times in the night orders were given to fall into line and the boys, expecting to advance, would examine their guns, see that everything was in shape for action, then be ordered to stack arms and lie down again.’
      • ‘Insert the muzzle of the other two rifles in there and stack arms.’

Phrasal Verbs

  • stack up

    • 1Form or cause to form a large quantity; build up.

      ‘cars stack up behind every bus, while passengers stand in line to pay fares’
      • ‘Most of these devices have large amounts of system memory, so multiple tasks can be stacked up at once, and their big hard disks (usually around the 20GB mark) make storing contact information a simple business.’
      • ‘In times of extreme deadline crisis, when deadlines are stacked up all around the office like unexploded ordinance, lack of attention to personal hygiene is a professional survival mechanism.’
      • ‘So I guess it counts for something then; it may not help stack the funds up in the bank account but at least the pressure can come off.’
      • ‘Straight away, after a cup of tea and an initial unpacking operation, stacking the washer up with a week's linen, he was off out to cut the grass.’
      • ‘When projects fall behind schedule, it seems to be because these particular employees are stacked up with work and can't adhere to the project schedule.’
      • ‘It's not even the rainy season - or what we used to qualify as the rainy season, as if we knew anything about it in the first place - but the storms are stacked up out over the Pacific like pool balls on a billiard table and not a pocket in sight.’
      • ‘Almost 1,000 people reported symptoms, and although no one died, every one of the 125 beds in the town's only hospital was filled, and patients were stacked up in the corridors.’
    • 2Measure up; compare.

      ‘our rural schools stack up well against their urban counterparts’
      • ‘Wade is only one season into his tour of duty, but he is stacking up well in comparison to his predecessors.’
      • ‘How does the Federal Reserve System stack up in comparison with other central banks?’
      • ‘How does your pay stack up… when compared to other facility professionals?’
      • ‘Find out how your income stacks up compared to the rest of the world.’
      • ‘It allows schools to receive comparison and external reviews to see how the institutions stack up, Blood says.’
      • ‘A look at how 1995 compares with other seasons shows how it stacks up against 1933 and other busy years.’
      • ‘I wonder how other state champs would stack up if measured the same way!’
      • ‘If funding is how the relative merits of departments and faculties were judged, then the humanities and social sciences stacked up poorly indeed compared to the practical disciplines.’
      • ‘And some say our nightlife doesn't stack up when compared to Leeds.’
      • ‘And how do they stack up compared to the rest of us on health care expenditures?’
      1. 2.1usually with negativeMake sense; correspond to reality.
        ‘to blame the debacle on the antics of a rogue trader is not credible—it doesn't stack up’
        • ‘Sorry but what you said just doesn't stack up with the odds.’
        • ‘Any way you look at it, the statement just doesn't stack up.’


Middle English: from Old Norse stakkr ‘haystack’, of Germanic origin.