Felonious

Adjective

 * 1) Having the quality of felony; malignant; malicious; villainous; traitorous; perfidious; being, relating to, or concerning felony
 * 2)  done with intent to commit a crime; as, felonious homicide.

Adverbs for Felonious
dastardly; outrageously; contemptibly; obviously; openly; heinously; infamously; basely; grossly; shamelessly; scandalously; brutally; atrociously; scurvily; diabolically; terribly; frightfully; horridly; insanely; venomously; fiendishly.

Synonyms for Felonious
criminal, malignant, malicious, evil, depraved, underhand, vile, villainous, traitorous, perfidious, malevolent, heinous, corrupt, harmful, noxious, injurious, wicked, perverse, base, vicious, wrong.

Antonyms for Felonious
good, noble, praiseworthy, generous, commendable, charitable, kind, decent, honorable, laudable, exalted, benevolent, beneficent, remedial, helpful, worthy, meritorious, advantageous.

Derived terms

 * feloniously adverb
 * feloniousness noun

Thesaurus
actionable, against the law, amoral, anarchic, anarchistic, anomic, black-market, bootleg, chargeable, conscienceless, contraband, contrary to law, corrupt, corrupted, criminal, crooked, dark, devious, dishonest, dishonorable, doubtful, dubious, evasive, evildoing, fishy, flawed, fraudulent, ill-got, ill-gotten, illegal, illegitimate, illicit, immoral, impermissible, indirect, iniquitous, insidious, irregular, justiciable, lawless, malefactory, malfeasant, nonconstitutional, nonlegal, nonlicit, not kosher, outlaw, outlawed, punishable, questionable, rotten, shady, shameless, shifty, sinful, sinister, slippery, suspicious, triable, tricky, unallowed, unauthorized, unconscienced, unconscientious, unconscionable, unconstitutional, under-the-counter, under-the-table, underhand, underhanded, unethical, unlawful, unofficial, unprincipled, unsavory, unscrupulous, unstatutory, unstraightforward, unwarrantable, unwarranted, wicked, without remorse, without shame, wrong, wrongdoing, wrongful