acrimonious
harsh or bitter in disposition, speech, or manner
anomalous
different from the usual or standard; hard to identify or classify because of abnormality
arduous
involving hard labor; to test one's endurance
extraneous
irrelevant to present topic; nonessential part
factitious
unauthentic or fabricated
libelous
involving untrue information that harms someone's reputation
noxious
physically or morally harmful
posthumous
occurring or appearing after one's death (as a child born after the death of its father, or a writing published after the death of the author)
pusillanimous
lacking in courage; characterized by weakness of spirit
querulous
given to complaining; full of complaints
raucous
harsh-sounding or loud; rambunctious and rowdy
surreptitious
taken or done stealthily or secretly; unauthorized