Synonyms for Objectionable (same or very similar meaning)
WordNet sense 1 (causing disapproval or protest):
obnoxious
WordNet sense 2 (unpleasant or disgusting especially to the senses):
offensive
WordNet sense 3 (liable to objection or debate; used of something one might take exception to):
exceptionable
WordNet sense 4 (not acceptable; not welcome):
unacceptable
From the ODE community, based on WordNet
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