Definition of jacket in English:



  • 1An outer garment extending either to the waist or the hips, typically having sleeves and a fastening down the front.

    • ‘At the time he had a goatee beard and was wearing a waist length jacket with maroon coloured sleeves, dark coloured jeans and dark coloured footwear.’
    • ‘He misjudged her reaction, and removed his leather jacket, enveloping her shoulders with it.’
    • ‘Suspicions were raised when a chamber maid saw documents in his jacket which contradicted his story.’
    • ‘I reached into the front pocket of my jacket and took out a small business card.’
    • ‘For evening, her navy tuxedo jacket has satin trim on the collar, pocket and sleeves, and is a modern twist on a classic design.’
    • ‘The 10 are then trained to operate speed guns identical to those used by police and kitted out with official-looking high-visibility jackets.’
    • ‘The popular lengths for jackets this fall are waist length, three-quarter length and trench coat length.’
    • ‘Get ready for the heat with the latest in outerwear; from trench coats to suede jackets.’
    • ‘The key here is to get her something between a jacket and a blazer that she can just throw on with any outfit.’
    • ‘Damian pulled out an envelope from his jacket and sat across from Stephanie, his other hand still holding onto her delicate fingers.’
    • ‘The jackets are skillfully constructed, whether impeccable blazers or little jackets with bouffant sleeves.’
    • ‘The mystery caller was stocky and dressed in a blouson jacket and a baseball cap.’
    • ‘Romanov pulled out a file folder from her jacket slowly, ensuring that the bodyguards saw what she held, and handed it to Mr. Devlin.’
    • ‘Like jean jackets, your jeans can be worn with multiple tops and shoe styles.’
    • ‘Often featuring a snap front and drawstring waist, this jacket maybe lined or unlined.’
    • ‘Jean skirts, jean jackets, and all lengths and styles of jeans can give your wardrobe great variety!’
    • ‘He unbuttoned the tuxedo jacket and rolled the sleeves to his elbows.’
    • ‘Jean grabs him by the lapel of his tuxedo jacket and narrows her green eyes at him.’
    • ‘Joy removed the matching boutonnière from its clear plastic container and pinned it on the lapel of his tuxedo jacket.’
    • ‘From leather jackets and blazers, to pants, yes, pants, learn to look stylish in the latest trend.’
    1. 1.1An outer covering, especially one placed around a tank or pipe to insulate it.
      • ‘If your water heater is located in an unheated space, bundle it up with an insulating jacket.’
      • ‘Similarly, a steel and concrete jacket was secured to the swing span central pier in 1936.’
      • ‘Bosch designed a thin inner liner of soft steel that sealed the gases in, its pressure load supported by a stout perforated steel jacket.’
      • ‘If you have a conventional water heater, give it a wrap as well with an insulated jacket that will help prevent energy loss.’
      • ‘Install an insulating jacket around the hot water heater to improve its heat retention capability.’
      wrapping, wrapper, wrap, sleeve, sheath, sheathing, envelope, cover, covering
      casing, case, shell, housing, encasement, capsule
      View synonyms
    2. 1.2A metal casing for a bullet.
      • ‘I test fired the Robar 228 with a wide variety of full metal jacket and hollow-point loads to test for reliability.’
      • ‘In 1948, the Nosler Partition Bullet Co. formed to make bullet jackets turned out one at a time on a lathe.’
      • ‘One of the reasons is that good match bullets often have thin jackets which can be more uniform and concentric.’
      • ‘The bullet was produced with a cupro-nickel jacket over a lead core.’
      • ‘The idea of an EFMJ is a bullet whose jacket is weakened from the inside so that it splits open on contact with a target.’
    3. 1.3The skin of a potato.
      ‘potatoes cooked in their jackets’
      • ‘What next, said the Herald, oranges with no peel, potatoes without jackets?’
      • ‘New season potatoes, baked in their jackets and dressed ever so slightly with olive oil are the best possible accompaniment to properly cooked burgers and a green salad.’
      • ‘All we ate every day was a piece of black bread and three potatoes cooked in their jackets.’
    4. 1.4The dust jacket of a book.
      • ‘You may not have heard of House Industries, but you will undoubtedly have seen their work, be it on book jackets, CD covers or in the typography of advertising.’
      • ‘The atmosphere is literary, with the walls covered in huge posters of book jackets of American literary masterpieces.’
      • ‘This week's review is a hard cover book with a hard-hitting jacket, determined to catch your attention.’
      • ‘A selection of books are on display with a summary of the story covering the book jacket.’
      • ‘Chris Moore lives in another world - but it's all in a day's work for the artist whose illustrations have been used on the book jackets of some of the world's top authors.’
      wrapping, wrapper, wrap, sleeve, sheath, sheathing, envelope, cover, covering
      casing, case, shell, housing, encasement, capsule
      View synonyms
    5. 1.5A record sleeve.
      • ‘While I gazed at walls decorated with faded record jackets, the owner enthralled me with his in-depth knowledge of this musical genre.’
      • ‘Record jackets of all types lined the walls and memorabilia from the rock and roll era filled the many shelves all around the establishment.’
      • ‘Nelly nodded looking over my shoulder at the titles on the jackets of the records.’
      wrapping, wrapper, wrap, sleeve, sheath, sheathing, envelope, cover, covering
      casing, case, shell, housing, encasement, capsule
      View synonyms
    6. 1.6A steel frame fixed to the seabed, forming the support structure of an oil production platform.


  • Cover with a jacket.

    • ‘For cladding-pumped laser experiments, some preforms have been jacketed with a second quartz glass tube in order to increase the cladding-core relation.’
    • ‘Old stoves have been jacketed and furnaces put in. Artificial lighting systems have been installed.’
    • ‘While most bullets have been jacketed with copper-zinc alloy, a variety of other hard metals, including tungsten, have been used.’


Late Middle English: from Old French jaquet, diminutive of jaque (see jack).