Synonyms for Unobjectionable (same or very similar meaning)
WordNet sense 1 (giving no offense):
inoffensive
WordNet sense 2 (not causing disapproval):
innocuous
WordNet sense 3 ((of behavior or especially language) free from objectionable elements; fit for all observers):
clean
WordNet sense 4 (worthy of acceptance or satisfactory):
acceptable
From the ODE community, based on WordNet
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