Antonyms of adj defamatory

1 sense of defamatory

Sense 1
calumniatory, calumnious, defamatory, denigrative, denigrating, denigratory, libellous, libelous, slanderous -- ((used of statements) harmful and often untrue; tending to discredit or malign)

INDIRECT (VIA harmful) -> harmless -- (not causing or capable of causing harm; "harmless bacteria"; "rendered the bomb harmless")

Similarity of adj defamatory

1 sense of defamatory

Sense 1
calumniatory, calumnious, defamatory, denigrative, denigrating, denigratory, libellous, libelous, slanderous -- ((used of statements) harmful and often untrue; tending to discredit or malign)
       => harmful (vs. harmless) -- (causing or capable of causing harm; "too much sun is harmful to the skin"; "harmful effects of smoking")