\Nine"ty\, a. [See {Nine}, and cf. {Forty}.]
Nine times ten; eighty-nine and one more; as, ninety men.

\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.
2. A symbol representing ninety units, as 90 or xc.