unacceptable (adjective) unacceptable: not suitable or satisfactory
Sinonime: below par,
damaged,
disagreeable, displeasing,
distasteful, exceptionable, half-baked, ill-favored,
improper, inadmissible, insupportable,
lousy*, not up to snuff, objectionable,
obnoxious,
offensive,
reject,
repugnant, unappealing,
undesirable, uninviting,
unpleasant,
unsatisfactory,
unwanted, unwelcome, won't do
Antonime: acceptable,
desirable,
ok,
satisfactory,
suitable