1. (a.) Not likely; improbable; not to be reasonably expected; as, an unlikely event; the thing you mention is very unlikely.

2. (a.) Not holding out a prospect of success; likely to fail; unpromising; as, unlikely means.

3. (a.) Not such as to inspire liking; unattractive; disagreeable.

4. (adv.) In an unlikely manner.

distasteful doubtable doubtful dubious dubitable hardly possible implausible improbable inappropriate inauspicious inconceivable incredible more than doubtful objectionable questionable remote unacceptable unattractive unbecoming uncongenial unfit unfitting unimaginable unpromising unpropitious unseemly unsuitable unthinkable