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

ninety \nine"ty\, a. see nine, and cf. forty.
   nine times ten; eighty-nine and one more; as, ninety men.
   1913 webster
see also:
nine forty 

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

ninety \nine"ty\, n.; pl. nineties.
   1. the sum of nine times ten; the number greater by a unit
      than eighty-nine; ninety units or objects.
      1913 webster

   2. a symbol representing ninety units, as 90 or xc.
      1913 webster
see also:
nineties 

[3] : WordNet (r) 2.0

ninety
     adj : being ten more than eighty syn: 90, xc
     n : the cardinal number that is the product of ten and nine
         syn: 90, xc
see also:
90 xc xc 

Ninety >> N Words
Ninety, definition of term: Ninety
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