From WordNet (r) 2.0 (August 2003) [wn]:
forty
adj : being ten more than thirty [syn: 40, xl, twoscore]
n : the cardinal number that is the product of ten and four
[syn: 40, XL]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Forty \For"ty\ (f[^o]r"t[y^]), a. [OE. forti, fourti, fowerti,
AS. fe['o]wertig; fe['o]wer four + suff. -tig ten; akin to
OS. fiwartig, fiartig, D. veertig, G. vierzig, Icel.
fj["o]rut[imac]u, Sw. fyratio, Dan. fyrretyve, Goth.
fidw[=o]r tigjus. See Four, and Ten, and cf. Fourteen.]
Four times ten; thirty-nine and one more.
[1913 Webster]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Forty \For"ty\, n.; pl. Forties (-t[i^]z).
1. The sum of four tens; forty units or objects.
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2. A symbol expressing forty units; as, 40, or xl.
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