unlikely (adj.)

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