cap

noun (1), often attributive

\ ˈkap

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

b(1) : pileus

(2) : calyptra

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

c British : cervical cap

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

verb

capped; 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