adjective
1.
Synonyms: insecure 1, unassured, unconfident
Antonyms: sure
2.
Synonyms: weak 2, dickey, fluctuant, insecure, rootless, shaky, unstable, vacillating, wavering, wobbly
3.
Synonyms: doubtful 1, borderline, dubious, indecisive, open, problematic, suspicious, uncertain, unclear, undecided
Antonyms: sure
4.
Synonyms: unreliable 1, dubious, fly-by-night, questionable, trustless, undependable, untrustworthy, untrusty