Definition of cap
(Entry 1 of 6)
1a : a head covering especially with a visor and no brim
b : a distinctive head covering emblematic of a position or office: such as
(1) : a cardinal's biretta
(2) : mortarboard
2 : a natural cover or top: such as
a : an overlying rock layer that is usually hard to penetrate
c : the top of a bird's head or a patch of distinctively colored feathers in this area
3a : something that serves as a cover or protection especially for a tip, knob, or end
a bottle cap
b : a fitting for closing the end of a tube
d : an artificial crown for a tooth
4 : an overlaying or covering structure
5 : a paper or metal container holding an explosive charge (as for a toy pistol)
6 : an upper limit (as on expenditures) : ceiling a cap on military spending
7 : the symbol ∩ indicating the intersection of two sets — compare cup sense 9
8 : a cluster of molecules or chemical groups bound to one end or a region of a cell, virus, or molecule
cap in hand
: in a respectful, humble, or sometimes fearful manner
went cap in hand to the governor to seek more funds for education
cap
verbcapped; capping
Definition of cap (Entry 2 of 6)
1a : to provide or protect with a cap
cap a bottle
b : to give a cap to as a symbol of honor, rank, or achievement
2 : to form a cap over : crown mountains capped with mist
3a : to follow with something more noticeable or more significant : outdo
b : to bring to a climax or conclusion
cap off the show with a song
4 : to form a chemical cap on
5 : to prevent from growing or spreading : set an upper limit on
cap oil prices
6 : to supply (a tooth) with an artificial crown
: to form or produce a chemical cap
cap
noun (2)Definition of cap (Entry 3 of 6)
: a small amount of an illegal or legally regulated drug especially : a small amount of a drug enclosed in a capsule a cap of cocaine
cap
noun (3) plural caps
Definition of cap (Entry 4 of 6)
2 : a capital letter
—usually plurala message written in capsAccording to [linguist Deborah] Tannen, women's preference for expressive hashtags is "similar to their using exclamation points, caps, and repetition of letters to show emphasis, and to the fact that women's spoken intonation patterns tend to vary more than men's."— Jessica BennettGood netiquette includes not using all caps [=exclusively capital letters] when typing, as it comes across as shouting.— John DeGarmo
cap
abbreviation (1)Definition of cap (Entry 5 of 6)
1 capacity
2 capital
3 capitalize; capitalized
CAP
abbreviation (2)Definition of CAP (Entry 6 of 6)
1 Civil Air Patrol
2 combat air patrol
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Time Traveler for cap
The first known use of cap was before the 12th century
See more words from the same century