The Collaborative International Dictionary of English v.0.48:

Troll \Troll\, v. t. [imp. & p. p. Trolled; p. pr. & vb. n.
   Trolling.] [OE. trollen to roll, F. tr[^o]ler, Of. troller
   to drag about, to ramble; probably of Teutonic origin; cf. G.
   trollen to roll, ramble, sich trollen to be gone; or perhaps
   for trotler, fr. F. trotter to trot (cf. Trot.). Cf.
   Trawl.]
   1. To move circularly or volubly; to roll; to turn.
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            To dress and troll the tongue, and roll the eye.
                                                  --Milton.
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   2. To send about; to circulate, as a vessel in drinking.
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            Then doth she troll to the bowl.      --Gammer
                                                  Gurton's
                                                  Needle.
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            Troll the brown bowl.                 --Sir W.
                                                  Scott.
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   3. To sing the parts of in succession, as of a round, a
      catch, and the like; also, to sing loudly or freely.
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            Will you troll the catch ?            --Shak.
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            His sonnets charmed the attentive crowd,
            By wide-mouthed mortaltrolled aloud.  --Hudibras.
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   4. To angle for with a trolling line, or with a book drawn
      along the surface of the water; hence, to allure.
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   5. To fish in; to seek to catch fish from.
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            With patient angle trolls the finny deep.
                                                  --Goldsmith.
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WordNet (r) 3.0 (2006):

trolling
    n 1: angling by drawing a baited line through the water [syn:
         troll, trolling]