cap

Dictionary definition · cap

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

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

Source: Open English WordNet (CC BY 4.0).