What is another word for "unlikelihood"?

Roget's Thesaurus (1911) lists these synonyms for "unlikelihood": against, all, any, aquila, are, bad, bare, bizarre, chance, contrary, doubtful, expectation, far, ghost, have, heavy, improbability, improbable, inconceivable, incredibility, incredible, infrequent, inimaginable, little, long, more, non, odds, out, pal, poor, possibility, rare, reasonable, scarcely, sight, small, strange, than, the.