The Collaborative International Dictionary of English v.0.48:

Bud \Bud\ (b[u^]d), n. [OE. budde; cf. D. bot, G. butze, butz,
   the core of a fruit, bud, LG. butte in hagebutte, hainbutte,
   a hip of the dog-rose, or OF. boton, F. bouton, bud, button,
   OF. boter to bud, push; all akin to E. beat. See Button.]
   1. (Bot.) A small protuberance on the stem or branches of a
      plant, containing the rudiments of future leaves, flowers,
      or stems; an undeveloped branch or flower.
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   2. (Biol.) A small protuberance on certain low forms of
      animals and vegetables which develops into a new organism,
      either free or attached. See Hydra.
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   Bud moth (Zool.), a lepidopterous insect of several
      species, which destroys the buds of fruit trees; esp.
      Tmetocera ocellana and Eccopsis malana on the apple
      tree.
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