cap

noun

1
a tight-fitting headdress
2
a top (as for a bottle)
3
something serving as a cover or protection
4
the upper part of a column that supports the entablature
5
(dentistry) dental appliance consisting of an artificial crown for a broken or decayed tooth
tomorrow my dentist will fit me for a crown
6
a mechanical or electrical explosive device or a small amount of explosive; can be used to initiate the reaction of a disrupting explosive
7
an upper limit on what is allowed
he put a ceiling on the number of women who worked for him
there was a roof on salaries
8
a protective covering that is part of a plant
9
a fruiting structure resembling an umbrella or a cone that forms the top of a stalked fleshy fungus such as a mushroom

1
restrict the number or amount of
We had to cap the number of people we can accept into our club
2
lie at the top of
Snow capped the mountains

Also useful for “cap”:Unscrambler— Turn loose letters into real words