Definitions from Wiktionary ( )

▸ adjective:  Unfavorable; negative; not good.
▸ adjective:  Not suitable or fitting.
▸ adjective:  Not appropriate, of manners etc.
▸ adjective:  Unhealthy; liable to cause health problems.
▸ adjective:  (chiefly applied to a person's state of health) Sickly, unhealthy, unwell.
▸ adjective:  (often childish) Not behaving; behaving badly; misbehaving; mischievous or disobedient.
▸ adjective:  Tricky; stressful; unpleasant.
▸ adjective:  (sometimes childish) Evil; wicked.
▸ adjective:  Faulty; not functional.
▸ adjective:  (of food) Spoiled, rotten, overripe.
▸ adjective:  (of breath) Malodorous; foul.
▸ adjective:  False; counterfeit; illegitimate.
▸ adjective:  Unskilled; of limited ability; not good.
▸ adjective:  Of poor physical appearance.
▸ adjective:  (informal) Bold and daring.
▸ adjective:  (slang) Good, superlative, excellent, cool.
▸ adjective:  (of a need, want, or pain) Severe, urgent.
▸ adjective:  (US, slang) Overly promiscuous, licentious.
▸ adjective:  (originally African-American Vernacular, slang, of a woman) Very attractive; hot, sexy.
▸ adjective:  (slang, of a draft/check) Not covered by funds on account.
▸ adjective:  (Internet slang, sarcastic) Used without a copula to mock people who oppose something without having any real understanding of it.
▸ adverb:  (now colloquial) Badly; poorly.
▸ adverb:  (intensifier) Badly; severely, extremely, passionately, eagerly.
▸ noun:  Something that is bad; a harm or evil.
▸ noun:  (slang, with possessive determiner) Error; mistake.
▸ noun:  (countable, uncountable, economics) An item (or kind of item) of merchandise with negative value; an unwanted good.
▸ verb:  (British, dialect, transitive) To shell (a walnut).

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