The Collaborative International Dictionary of English v.0.48:

Sprout \Sprout\ (sprout), v. i. [imp. & p. p. Sprouted; p. pr.
   & vb. n. Sprouting.] [OE. sprouten, spruten; akin to
   OFries. spr[=u]ta, AS. spre['o]tan, D. spruiten, G.
   spriessen, Sw. spruta to squirt, to spout. Cf. Sprit, v. t.
   & i., Sprit a spar, Spout, v. t., Spurt.]
   1. To shoot, as the seed of a plant; to germinate; to push
      out new shoots; hence, to grow like shoots of plants.
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   2. To shoot into ramifications. [Obs.] --Bacon.
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The Collaborative International Dictionary of English v.0.48:

Sprout \Sprout\, v. t.
   1. To cause to sprout; as, the rain will sprout the seed.
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   2. To deprive of sprouts; as, to sprout potatoes.
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The Collaborative International Dictionary of English v.0.48:

Sprout \Sprout\, n. [Cf. AS. sprote a sprout, sprig; akin to
   Icel. sproti, G. sprosse. See Sprout, v. i.]
   1. The shoot of a plant; a shoot from the seed, from the
      stump, or from the root or tuber, of a plant or tree; more
      rarely, a shoot from the stem of a plant, or the end of a
      branch.
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   2. pl. Young coleworts; Brussels sprouts. --Johnson.
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   Brussels sprouts (Bot.) See under Brussels.
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WordNet (r) 3.0 (2006):

sprout
    n 1: any new growth of a plant such as a new branch or a bud
    2: a newly grown bud (especially from a germinating seed)
    v 1: produce buds, branches, or germinate; "the potatoes
         sprouted" [syn: shoot, spud, germinate, pullulate,
         bourgeon, burgeon forth, sprout]
    2: put forth and grow sprouts or shoots; "the plant sprouted
       early this year" [syn: sprout, stock]