Definition of "Cap" :
noun: a tight-fitting headdress
noun: a top (as for a bottle)
noun: something serving as a cover or protection
noun: the upper part of a column that supports the entablature
noun: (dentistry) dental appliance consisting of an artificial crown for a broken or decayed tooth
noun: a mechanical or electrical explosive device or a small amount of explosive; can be used to initiate the reaction of a disrupting explosive
noun: an upper limit on what is allowed
"They established a cap for prices."
noun: a protective covering that is part of a plant
noun: a fruiting structure resembling an umbrella or a cone that forms the top of a stalked fleshy fungus such as a mushroom
verb: restrict the number or amount of
"We had to cap the number of people we can accept into our club."
verb: lie at the top of
"Snow capped the mountains."