THESAURUS
one and only
I, absolute, ace, alone, atom, azygous, celibate, first and last, impair, lone, monad, no other, none else, nothing else, nought beside, odd, one, only, only-begotten, singular, sole, unique, unit, unpaired, unrepeated
ROGET THESAURUS
one and only
Identity
N
identity, sameness, coincidence, coalescence, convertibility, equality, selfness, self, oneself, identification, monotony, tautology, facsimile, homoousia: alter ego, ipsissima verba, same, self, very, one and the same, very thing, actual thing, real McCoy, no other,
one and only, in the flesh, identical, self, ilk, the same, selfsame, one and the same, homoousian, coincide, coalescent, coalescing, indistinguishable, one, equivalent, tweedle dee and tweedle dum, much the same, of a muchness, unaltered, identically, on all fours.