What does CAP mean?

noun

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