cap in WordNet English dictionary

1. a tight-fitting headdress
   cap 
   
2. the upper part of a column that supports the entablature
   capital  chapiter  cap 
   
3. a top (as for a bottle)
   cap 
   
4. something serving as a cover or protection
   cap 
   
5. (dentistry) dental appliance consisting of an artificial crown for a broken or decayed tooth
   "tomorrow my dentist will fit me for a crown"
   crown  crownwork  jacket  jacket crown  cap 
   
6. a mechanical or electrical explosive device or a small amount of explosive; can be used to initiate the reaction of a disrupting explosive
   detonator  detonating device  cap 
   
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"; "they established a cap for prices"
   ceiling  roof  cap 
   
8. a protective covering that is part of a plant
   hood  cap 
   
9. a fruiting structure resembling an umbrella or a cone that forms the top of a stalked fleshy fungus such as a mushroom
   cap  pileus 
   

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