See more 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.
  3. mobcap.
  4. a headdress denoting rank, occupation, religious order, or the like: a nurse's cap.
  5. mortarboard(def 2).
  6. Mathematics. the symbol ∩, used to indicate the intersection of two sets.Compare intersection(def 3a).
  7. anything resembling or suggestive of a covering for the head in shape, use, or position: a cap on a bottle.
  8. summit; top; acme.
  9. 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.
  10. Mycology. the pileus of a mushroom.
  11. Botany. calyptra(def 1).
  12. Mining. a short, horizontal beam at the top of a prop for supporting part of a roof.
  13. a percussion cap.
  14. British Sports. a selection for a representative team, usually for a national squad.
  15. a noise-making device for toy pistols, made of a small quantity of explosive wrapped in paper or other thin material.
  16. 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.
  17. a new tread applied to a worn pneumatic tire.
  18. Architecture. a capital.
  19. Carpentry. a metal plate placed over the iron of a plane to break the shavings as they rise.
  20. Fox Hunting. capping fee.
  21. 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.
  3. follow up with something as good or better; surpass; outdo: to cap one joke with another.
  4. to serve as a cap, covering, or top to; overlie.
  5. to put a maximum limit on (prices, wages, spending, etc.).
  6. 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.
  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

before 1000; Middle English cappe, Old English cæppe < Late Latin cappa hooded cloak, cap; cf. cape1
Related formscap·less, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Related Words for set one's cap for

pursue, cultivate, solicit, rush, court, propose, beg, importune, entreat, spoon, caress, charm, address, date, spark, chase

British Dictionary definitions for set one's cap for


  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, etca nurse's cap
  3. something that protects or covers, esp a small lid or coverlens cap
  4. an uppermost surface or partthe cap of a wave
    1. See percussion cap
    2. a small amount of explosive enclosed in paper and used in a toy gun
  5. sport, mainly British
    1. an emblematic hat or beret given to someone chosen for a representative teamhe has won three England caps
    2. a player chosen for such a team
  6. the upper part of a pedestal in a classical order
  7. the roof of a windmill, sometimes in the form of a dome
  8. botany the pileus of a mushroom or toadstool
  9. hunting
    1. 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
    2. a collection taken at a meet of hounds, esp for a charity
  10. anatomy
    1. the natural enamel covering a tooth
    2. an artificial protective covering for a tooth
  11. See Dutch cap (def. 2)
  12. an upper financial limit
  13. a mortarboard when worn with a gown at an academic ceremony (esp in the phrase cap and gown)
  14. meteorol
    1. the cloud covering the peak of a mountain
    2. the transient top of detached clouds above an increasing cumulus
  15. cap in hand humbly, as when asking a favour
  16. if the cap fits British the allusion or criticism seems to be appropriate to a particular person
  17. set one's cap for or set one's cap at (of a woman) to be determined to win as a husband or lover
verb caps, capping or capped (tr)
  1. to cover, as with a capsnow capped the mountain tops
  2. informal to outdo; excelyour story caps them all; to cap an anecdote
  3. to cap it all to provide the finishing touchwe had sun, surf, cheap wine, and to cap it all a free car
  4. sport, British to select (a player) for a representative teamhe was capped 30 times by Scotland
  5. to seal off (an oil or gas well)
  6. to impose an upper limit on the level of increase of (a tax, such as the council tax)rate-capping
  7. hunting to ask (hunt followers) for a cap
  8. mainly Scot and NZ to award a degree to
Derived Formscapper, noun

Word Origin for cap

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


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

Word Origin and History for set one's cap for



c.1400, "to put a cap on," from cap (n.). Meaning "cover as with s cap" is from c.1600. Figurative sense of "go one better" is from 1580s. Related: Capped; capping.



late Old English cæppe "hood, head-covering, cape," from Late Latin cappa "a cape, hooded cloak" (source of Spanish capa, Old North French cape, French chape), possibly a shortened from capitulare "headdress," from Latin caput "head" (see head (n.)).

Meaning "women's head covering" is early 13c. in English; extended to men late 14c. Figurative thinking cap is from 1839 (considering cap is 1650s). Of cap-like coverings on the ends of anything (e.g. hub-cap) from mid-15c. Meaning "contraceptive device" is first recorded 1916. That of "cap-shaped piece of copper lined with gunpowder and used to ignite a firearm" is c.1826; extended to paper version used in toy pistols, 1872 (cap-pistol is from 1879).

The Late Latin word apparently originally meant "a woman's head-covering," but the sense was transferred to "hood of a cloak," then to "cloak" itself, though the various senses co-existed. Old English took in two forms of the Late Latin word, one meaning "head-covering," the other "ecclesiastical dress" (see cape (n.1)). In most Romance languages, a diminutive of Late Latin cappa has become the usual word for "head-covering" (e.g. French chapeau).

Online Etymology Dictionary, © 2010 Douglas Harper

set one's cap for in Medicine


  1. A protective cover or seal, especially one that closes off an end or a tip and that resembles a close-fitting head covering.


  1. catabolite gene activator protein
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Idioms and Phrases with set one's cap for

set one's cap for

Pursue someone romantically, as in We all thought Anne had set her cap for Joe, but we were wrong. In the 1700s this term, which may have alluded to donning one's best headgear, was applied to members of either sex, but by the early 1800s it generally described a woman chasing a man. It is probably obsolescent.


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.