A cap is a hat that fits snugly on your head. You might wear a bathing cap when you swim, to keep your hair dry.

Many caps don't have brims, while hats often do. You can even describe someone's hair using the word cap: "She has a glossy cap of dark hair." Another kind of cap is a lid: "Put the cap back on the ginger ale or it'll go flat!" And to cap is to limit, as when a school caps the number of students at 500. The root is the Latin word caput, or "head."

Definitions of cap
  1. noun
    a tight-fitting headdress
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    balaclava, balaclava helmet
    a cap that is close-fitting and woolen and covers all of the head but the face
    Balmoral, bluebonnet
    a brimless dark blue Scottish cap with a flat top and a plume on one side
    baseball cap, golf cap, jockey cap
    a cap with a bill
    bathing cap, swimming cap
    a tight-fitting cap that keeps hair dry while swimming
    a cap with no brim or bill; made of soft cloth
    a child's tight-fitting cap; often ties under the chin
    berretta, biretta, birretta
    a stiff cap with ridges across the crown; worn by Roman Catholic clergy
    calpac, calpack, kalpac
    a high-crowned black cap (usually made of felt or sheepskin) worn by men in Turkey and Iran and the Caucasus
    cloth cap, flat cap
    a flat woolen cap with a stiff peak
    cockscomb, coxcomb
    a cap worn by court jesters; adorned with a strip of red
    coonskin, coonskin cap
    a raccoon cap with the tail hanging down the back
    fez, tarboosh
    a felt cap (usually red) for a man; shaped like a flat-topped cone with a tassel that hangs from the crown
    garrison cap, overseas cap
    a wedge-shaped wool or cotton cap; worn as part of a uniform
    a Scottish cap with straight sides and a crease along the top from front to back; worn by Highlanders as part of military dress
    a cap that is wrapped around by a turban and worn by Muslim religious elders
    kepi, peaked cap, service cap, yachting cap
    a cap with a flat circular top and a visor
    liberty cap
    close-fitting conical cap worn as a symbol of liberty during the French Revolution and in the U.S. before 1800
    large high frilly cap with a full crown; formerly worn indoors by women
    an academic cap with a flat square with a tassel on top
    a cloth cap worn in bed
    a woman's cap with two long flaps pinned on
    sailor cap
    a cap worn by sailors
    shower cap
    a tight cap worn to keep hair dry while showering
    ski cap, stocking cap, toboggan cap
    a close-fitting woolen cap; often has a tapering tail with a tassel
    rounded brimless cap fitting the crown of the head
    tam, tam-o'-shanter, tammy
    a woolen cap of Scottish origin
    watch cap
    a knitted dark blue wool cap worn by seamen in cold or stormy weather
    wishing cap
    a magical cap that secures whatever one wishes for
    beanie, beany
    a small skullcap; formerly worn by schoolboys and college freshmen
    a skullcap worn by nuns under a veil or by soldiers under a hood of mail or formerly by British sergeants-at-law
    yarmelke, yarmulka, yarmulke
    a skullcap worn by religious Jews (especially at prayer)
    type of:
    headdress, headgear
    clothing for the head
  2. noun
    something serving as a cover or protection
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    distributor cap
    the cap of the distributor that holds in place the wires from the distributor to the spark plugs
    collet, ferrule
    a metal cap or band placed on a wooden pole to prevent splitting
    cap that fits over the hub of a wheel
    lens cap, lens cover
    cap used to keep lens free of dust when not in use
    a small metal cap to protect the finger while sewing; can be used as a small container
    type of:
    protection, protective cover, protective covering
    a covering that is intend to protect from damage or injury
  3. noun
    a top (as for a bottle)
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    a cap that seals a bottle
    a flexible cap on a baby's feeding bottle or pacifier
    radiator cap
    cap on the opening in the top of a radiator through which a coolant liquid can be added
    type of:
    cover, top
    covering for a hole (especially a hole in the top of a container)
  4. noun
    (dentistry) dental appliance consisting of an artificial crown for a broken or decayed tooth
    synonyms: crown, crownwork, jacket, jacket crown
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    type of:
    dental appliance
    a device to repair teeth or replace missing teeth
  5. noun
    a protective covering that is part of a plant
    synonyms: hood
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    type of:
    cover, covering, natural covering
    a natural object that covers or envelops
  6. noun
    a fruiting structure resembling an umbrella or a cone that forms the top of a stalked fleshy fungus such as a mushroom
    synonyms: pileus
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    type of:
    plant part, plant structure
    any part of a plant or fungus
  7. noun
    the upper part of a column that supports the entablature
    synonyms: capital, chapiter
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    type of:
    the upper part of anything
  8. verb
    lie at the top of
    “Snow capped the mountains”
    synonyms: crest
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    type of:
    be located or situated somewhere; occupy a certain position
  9. noun
    an upper limit on what is allowed
    “they established a cap for prices”
    synonyms: ceiling, roof
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    glass ceiling
    a ceiling based on attitudinal or organizational bias in the work force that prevents minorities and women from advancing to leadership positions
    type of:
    the economic policy of controlling or limiting or curbing prices or wages etc.
  10. verb
    restrict the number or amount of
    “We had to cap the number of people we can accept into our club”
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    type of:
    circumscribe, confine, limit
    restrict or confine, "I limit you to two visits to the pub a day"
  11. noun
    a mechanical or electrical explosive device or a small amount of explosive; can be used to initiate the reaction of a disrupting explosive
    synonyms: detonating device, detonator
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    blasting cap
    a small tube filled with detonating substances; used to detonate high explosives
    percussion cap
    a detonator that explodes when struck
    type of:
    explosive device
    device that bursts with sudden violence from internal energy
Word Family

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