Definition of sump in US English:



  • 1A pit or hollow in which liquid collects, especially one in the floor of a mine or basement.

    • ‘At the bottom a stream runs along the floor and into the foam topped sump.’
    • ‘Provision has also been made for changing rooms and for a plant room for the swimming pool, a wrap-around deck, new entrance gates, a biocycle waste unit and a sump to accommodate the swimming pool overflow.’
    • ‘The same water after filtration, can be directed to flow into a recharge well or the underground sump.’
    • ‘The third day, we ascended to 14,000-foot Mawenzi Tarn, a mucky natural sump nestled against the jagged brown peak of Mawenzi itself.’
    • ‘Natural light seeps through to every sump, and it is magical to drift through the maze of stalactites studded with reflective crystals, the light dancing in the beams of our torches.’
    • ‘Besides providing a depository for the neighbouring heavy metals refinery, Bleak Pond forms a natural sump for the surrounding agricultural land, so harbours little aquatic life.’
    • ‘On surfacing in the lake at the far end I didn't quite make it out of the water and sank back down to the bottom of the sump.’
    • ‘Seepage of groundwater into the shaft from the shaft penetrations is currently collected by a system of gravity feed lines into sumps and tanks at mine level and subsequently pumped to the ground surface for disposal.’
    • ‘Often, when a house with a basement has a sump pump to remove unwanted water, the sump can be capped so that it can continue to drain water and serve as the location for a radon suction pipe.’
    • ‘On that basis I had decided when I started caving that the ‘reckless’ practice undertaken by cavers of free-diving sumps was not for me.’
    • ‘Rain seeping through the ground into your basement or crawl space may appear as damp, moldy walls or may be handled by a sump pump.’
    • ‘The climb lands in a pool, from which the water flows off left and down a steep shaft for 10m to a little sump.’
    • ‘All the leachate drains by gravity from the leachate collection layer to a sump, from which it is pumped out of the landfill for treatment and disposal.’
    • ‘Putting these pipes in a covered lined trench with a high level alarm, protected collection sump, is the only way of being sure of not causing off-site contamination.’
    • ‘The firm also claimed that each skip had four drainage holes to allow waste liquid to drain into a sump.’
    • ‘The character of the cave changes, and from here to the sump, the stream flows in a large tunnel.’
    • ‘Back then there were not many cave divers active in the Yorkshire Dales and most sumps were virtually unexplored.’
    • ‘For years, I'd been rather paranoid about water, avoiding sumps and ducks as much as possible.’
    • ‘The worst contamination was in the sump where leachate from the 230-acre site gathers before it is pumped back to the top of the tip, a council spokesman said.’
    • ‘Limited excavations have opened up gutters and a sump pool used to drain the caverns of groundwater.’
    marsh, marshland, swamp, swampland, mire, quagmire, quag, morass, slough, fen, fenland, wetland, carr
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    1. 1.1 A cesspool.
      • ‘If all houses and apartment complexes keep their water tanks and sumps clean and treated with chlorine frequently, mosquito breeding can be prevented to an extent.’
      • ‘A 15-foot-deep sewage sump close to the lake will affect ground water and the aquifer (a water-bearing stratum of earth).’
      • ‘‘No power in our house also means we cannot pump water from the sumps to the tank,’ Mukund, a resident, complained.’
      • ‘A waste sump overflowed in September causing hundreds of gallons of contaminated water to pour into the Gullielands Burn which flows through the Chapelcross site.’
      • ‘If my sump pump spewed sewage through my neighbor's basement window, it might be argued with some justification that I should cover her Rug Doctor rental.’
  • 2The base of an internal combustion engine, which serves as a reservoir of oil for the lubrication system.

    • ‘The impact cracked the sump and although the crew tried to make repairs on the following liaison section, the oil leaked from the engine and they retired.’
    • ‘The front diff bolts directly to the engine's oil sump.’
    • ‘One car's sump was seriously damaged by obstacles left in roadways by skateboarders.’
    • ‘Beneath the body was a dark liquid stain that looked as if it might have been left by oil dripped from the leaky sump of a parked car or an evaporated puddle of rainwater.’
    • ‘Precisely how an engine is sealed will depend on its layout, but typically we will link the cam covers to the cylinder heads, and the sump to the block.’
    • ‘Older engines used a camshaft located in the sump near the crankshaft.’
    • ‘The Tribunal found that the vehicle was seriously damaged: a hole was blown in the sump.’
    • ‘The oil will not have time to drain to the sump, so in this case it's better to turn the engine off and start it again later.’
    • ‘They prevent the fuel/air mixture and exhaust in the combustion chamber from leaking into the sump during compression and combustion.’
    • ‘The wall will route the oil selectively to the oil sump, simultaneously separating it from the crankcase to minimize oil foaming.’
    • ‘‘I nearly ripped off the sump on the curbs, and I was so worried about the car I went off the track at the next corner,’ says James.’
    • ‘There is also a ladder frame assembly between the sump and crankcase.’
    • ‘It can run past the rings and cause the motor to bend rods, which is very costly and makes a mess in the water when the oil sump is ruptured.’
    • ‘After such a long time in storage, all the oil will have drained to the sump.’
    • ‘One simple way to monitor leakage is to draw a chalk line in your sump to record its containment level and check it regularly for any unplanned loss.’
    • ‘A new cast-aluminum oil sump for the V - 6 improves both cooling performance and off-road damage resistance.’
    • ‘Tomlinson co-drives for his son Adam in an MG Midget, and they hit trouble on the 17-mile Radnor stage when they cracked the sump towards the end of the stage.’
    • ‘At the moment, the closest most engine analysts get is taking average readings from the piston crank and the oil sump.’
    • ‘These will get into the oil where they will be collected by the oil filter and a filter in the sump, which means any debris is unlikely to stay in the engine for long.’
    • ‘Also set in stone were the cylinder bore diameter, the block's minimum deck height, and the minimum distance from the crank centerline to the sump.’
    receptacle, container, holder, repository, tank
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Middle English (in the sense ‘marsh’): from Middle Dutch or Low German sump, or (in the mining sense) from German Sumpf; related to swamp.