unlikely

adjective, un·like·li·er, un·like·li·est.

1. not likely to be or occur; improbable; marked by doubt.
2. holding little prospect of success; unpromising; likely to fail: He is an unlikely candidate for reelection.
3. not ingratiating; objectionable.

adverb

4. in an unlikely way.

adjective

1. not likely; improbable

adj.late 14c., “not likely to occur,” from un- (1) + likely. Cf. Old Norse ulikligr, Middle Danish uligelig. Meaning “not likely to be true” is recorded from 1590s. see in the unlikely event.