Synonyms for Dishonorable (same or very similar meaning)
WordNet sense 1 (not adhering to ethical or moral principles):
base, immoral, unethical, dishonourable
WordNet sense 2 (contrary to conscience or morality or law):
wrong
WordNet sense 3 (completely lacking nobility in character or quality or purpose):
ignoble
WordNet sense 4 (mean and unworthy and despicable):
shabby
WordNet sense 5 ((used of conduct or character) deserving or bringing disgrace or shame):
disgraceful, ignominious, inglorious, shameful
WordNet sense 6 (intended to deceive):
deceitful, fraudulent
WordNet sense 7 (deceptive or fraudulent; disposed to cheat or defraud or deceive):
dishonest
From the ODE community, based on WordNet
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