Fifty \Fif"ty\, a. [AS. f[=i]ftig; akin to OHG. finfzug, fimfzuc, G. f["u]nfzig, funfzig, Goth. fimftigjus. See Five, and Ten, and cf. Fifteen.]

Five times ten; as, fifty men.

Source: Webster's Revised Unabridged Dictionary (1913)
 

Fifty \Fif"ty\, n.; pl. Fifties.

1. The sum of five tens; fifty units or objects.

2. A symbol representing fifty units, as 50, or l.

Source: Webster's Revised Unabridged Dictionary (1913)