[1] : The Collaborative International Dictionary of English v.0.48

hexad \hex"ad\, n. l. hexas, hexadis, the number six, gr. ?, ?,
   fr. "e`x six. chem.
   an atom whose valence is six, and which can be theoretically
   combined with, substituted for, or replaced by, six monad
   atoms or radicals; as, sulphur is a hexad in sulphuric acid.
   also used as an adjective.
   1913 webster

[2] : WordNet (r) 2.0

hexad
     n : the cardinal number that is the sum of five and one syn: six,
          6, vi, sixer, sise, captain hicks, half a
         dozen, sextet, sestet, sextuplet
see also:
six 6 vi sixer sise captain hicks 
half a dozen sextet sestet sextuplet 

Hexad >> H Words
Hexad, definition of term: Hexad
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