From WordNet (r) 3.0 (2006):
1
adj 1: used of a single unit or thing; not two or more; "`ane'
is Scottish" [syn: one, 1, i, ane]
n 1: the smallest whole number or a numeral representing this
number; "he has the one but will need a two and three to go
with it"; "they had lunch at one" [syn: one, 1, I,
ace, single, unity]