A buck is an adult male deer, antelope, reindeer, or rabbit. You can usually tell a buck by its large horns. If it’s a bunny, you just have to ask. A buck is also slang for an American dollar.

Full-grown male kangaroos are bucks, too. When a male animal is a buck, the female is a doe. A buck is a male deer, and so a doe is a female deer. When it's used as a verb, buck means to move in an abrupt, jerky way — when a horse bucks, it jumps and kicks its back legs out behind it. If someone bucks the system, they’re pushing against it. Colloquially, "to buck up” means to cheer up.

Definitions of buck
  1. noun
    mature male of various mammals (especially deer or antelope)
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    adult male deer
    royal, royal stag
    stag with antlers of 12 or more branches
    type of:
    eutherian, eutherian mammal, placental, placental mammal
    mammals having a placenta; all mammals except monotremes and marsupials
  2. verb
    jump vertically, with legs stiff and back arched
    synonyms: hitch, jerk
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    type of:
    move so as to change position, perform a nontranslational motion
  3. verb
    move quickly and violently
    synonyms: charge, shoot, shoot down, tear
    dart, dash, flash, scoot, scud, shoot
    run or move very quickly or hastily
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    move precipitously or violently
    type of:
    belt along, bucket along, cannonball along, hasten, hie, hotfoot, pelt along, race, rush, rush along, speed, step on it
    move fast
  4. verb
    buck the trend”
    synonyms: go against
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    type of:
    oppose, react
    act against or in opposition to
  5. verb
    to strive with determination
    “John is bucking for a promotion”
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    type of:
    endeavor, endeavour, strive
    attempt by employing effort
  6. noun
    a piece of paper money worth one dollar
    synonyms: clam, dollar, dollar bill, one dollar bill
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    type of:
    Federal Reserve note, bank bill, bank note, banker's bill, banknote, bill, government note, greenback, note
    a piece of paper money (especially one issued by a central bank)
  7. noun
    a framework for holding wood that is being sawed
    synonyms: horse, sawbuck, sawhorse
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    sawhorses used in pairs to support a horizontal tabletop
    type of:
    a structure supporting or containing something
  8. noun
    a gymnastic horse without pommels and with one end elongated; used lengthwise for vaulting
    synonyms: long horse, vaulting horse
    see moresee less
    type of:
    gymnastic horse, horse
    a padded gymnastic apparatus on legs
Word Family

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