From WordNet (r) 3.0 (2006):
unity
n 1: an undivided or unbroken completeness or totality with
nothing wanting; "the integrity of the nervous system is
required for normal development"; "he took measures to
insure the territorial unity of Croatia" [syn: integrity,
unity, wholeness]
2: 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]
3: the quality of being united into one [syn: oneness,
unity]