[ kap ]
See synonyms for cap on
  1. a close-fitting covering for the head, usually of soft supple material and having no visor or brim.

  2. a brimless head covering with a visor, as a baseball cap.

  1. a mobcap.

  2. a headdress denoting rank, occupation, religious order, or the like: a nurse's cap.

  3. Mathematics. the symbol ∩, used to indicate the intersection of two sets.: Compare intersection (def. 3a).

  4. anything resembling or suggestive of a covering for the head in shape, use, or position: a cap on a bottle.

  5. a maximum limit, as one set by law or agreement on prices, wages, spending, etc., during a certain period of time; ceiling: a 9 percent cap on pay increases for this year.

  6. Mycology. the pileus of a mushroom.

  7. Mining. a short, horizontal beam at the top of a prop for supporting part of a roof.

  8. British Sports. a selection for a representative team, usually for a national squad.

  9. a noise-making device for toy pistols, made of a small quantity of explosive wrapped in paper or other thin material.

  10. Nautical. a fitting of metal placed over the head of a spar, as a mast or bowsprit, and having a collar for securing an additional spar.

  11. a new tread applied to a worn pneumatic tire.

  12. Architecture. a capital.

  13. Carpentry. a metal plate placed over the iron of a plane to break the shavings as they rise.

  14. Fox Hunting. capping fee.

  15. Chiefly British Slang. a contraceptive diaphragm.

verb (used with object),capped, cap·ping.
  1. to provide or cover with or as if with a cap.

  2. to complete.

  1. follow up with something as good or better; surpass; outdo: to cap one joke with another.

  2. to serve as a cap, covering, or top to; overlie.

  3. to put a maximum limit on (prices, wages, spending, etc.).

  4. British Sports. to select (a player) for a representative team.

verb (used without object),capped, cap·ping.
  1. Fox Hunting. to hunt with a hunting club of which one is not a member, on payment of a capping fee.

Idioms about cap

  1. cap in hand, humbly; in supplication: He went to his father cap in hand and begged his forgiveness.

  2. set one's cap for, to pursue as being a potential mate.

Origin of cap

First recorded before 1000; Middle English cappe “headdress, hat, cap,” Old English cæppe “hood, cape, cope,” from Late Latin cappa “hooded cloak, cap”; cf. cape1

Other words from cap

  • capless, adjective

Other definitions for cap (2 of 7)

[ kap ]

  1. Usually caps . uppercase: Please set the underlined in caps.

verb (used with object),capped, cap·ping.
  1. to write or print in capital letters, or make an initial letter a capital; capitalize.

Origin of cap

First recorded in 1895–1900; by shortening

Other definitions for cap (3 of 7)

[ kap ]

  1. a capsule, especially of a narcotic drug.

Origin of cap

First recorded in 1940–45; by shortening of capsule

Other definitions for CAP (4 of 7)


  1. Common Agricultural Policy: a coordinated system established in 1960 by the European Economic Community for stabilizing prices of farm products of its member countries.

  1. computer-aided publishing.

  2. Stock Exchange. convertible adjustable preferred (stock).

  • Also C.A.P. (for defs. 1, 2, 4) .

Other definitions for cap. (5 of 7)


  1. (in prescriptions) let the patient take.

Origin of cap.

From the Latin word capiat

Other definitions for cap. (6 of 7)


  1. chapter.

Origin of cap.

From Latin capitulum “small head, capital of a column, cross beam” or Latin caput “head, to, summit, person”

Other definitions for cap. (7 of 7)


  1. capacity.

  2. capital.

  1. capitalize.

  2. capitalized.

  3. capital letter.

  4. foolscap. Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

How to use cap in a sentence

British Dictionary definitions for cap (1 of 3)


/ (kæp) /

  1. a covering for the head, esp a small close-fitting one made of cloth or knitted

  2. such a covering serving to identify the wearer's rank, occupation, etc: a nurse's cap

  1. something that protects or covers, esp a small lid or cover: lens cap

  2. an uppermost surface or part: the cap of a wave

    • a small amount of explosive enclosed in paper and used in a toy gun

  3. sport, mainly British

    • an emblematic hat or beret given to someone chosen for a representative team: he has won three England caps

    • a player chosen for such a team

  4. the upper part of a pedestal in a classical order

  5. the roof of a windmill, sometimes in the form of a dome

  6. botany the pileus of a mushroom or toadstool

  7. hunting

    • money contributed to the funds of a hunt by a follower who is neither a subscriber nor a farmer, in return for a day's hunting

    • a collection taken at a meet of hounds, esp for a charity

  8. anatomy

    • the natural enamel covering a tooth

    • an artificial protective covering for a tooth

  9. an upper financial limit

  10. a mortarboard when worn with a gown at an academic ceremony (esp in the phrase cap and gown)

  11. meteorol

    • the cloud covering the peak of a mountain

    • the transient top of detached clouds above an increasing cumulus

  12. cap in hand humbly, as when asking a favour

  13. if the cap fits British the allusion or criticism seems to be appropriate to a particular person

  14. set one's cap for or set one's cap at (of a woman) to be determined to win as a husband or lover

verbcaps, capping or capped (tr)
  1. to cover, as with a cap: snow capped the mountain tops

  2. informal to outdo; excel: your story caps them all; to cap an anecdote

  1. to cap it all to provide the finishing touch: we had sun, surf, cheap wine, and to cap it all a free car

  2. sport, British to select (a player) for a representative team: he was capped 30 times by Scotland

  3. to seal off (an oil or gas well)

  4. to impose an upper limit on the level of increase of (a tax, such as the council tax): rate-capping

  5. hunting to ask (hunt followers) for a cap

  6. mainly Scot and NZ to award a degree to

Origin of cap

Old English cæppe, from Late Latin cappa hood, perhaps from Latin caput head

Derived forms of cap

  • capper, noun

British Dictionary definitions for CAP (2 of 3)


abbreviation for
  1. Common Agricultural Policy: (in the EU) the system for supporting farm incomes by maintaining agricultural prices at agreed levels

British Dictionary definitions for cap. (3 of 3)


abbreviation for
  1. capital

  2. capitalize

  1. capitalization

  2. capital letter

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Idioms and Phrases with cap


In addition to the idioms beginning with cap

  • cap and gown
  • cap in hand
  • cap it all

also see:

  • feather in one's cap
  • hat (cap) in hand
  • if the shoe (cap) fits, wear it
  • put on one's thinking cap
  • set one's cap for

Also see underhat.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.