tau

from WordNet (r) 3.0 (2006)

tau
    n 1: the 19th letter of the Greek alphabet

from The Collaborative International Dictionary of English v.0.48

Tau \Tau\ (tou), n. [Gr. tay^.]
   The nineteenth letter ([Tau], [tau]) of the Greek alphabet,
   equivalent to English t.
   [Webster 1913 Suppl.]

from The Collaborative International Dictionary of English v.0.48

Tau \Tau\, n. [Gr. tay^ the letter [tau] (English {T}).] (Zool.)
   The common American toadfish; -- so called from a marking
   resembling the Greek letter tau ([tau]).
   [1913 Webster]

   {Tau cross}. See Illust. 6, of {Cross}.
      [1913 Webster]

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