[1] : 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.

[2] : 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
see also:
t tau cross cross 

[3] : WordNet (r) 2.0

tau
     n : the 19th letter of the greek alphabet

Tau >> T Words
Tau, definition of term: Tau
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