adj

• (chiefly applied to a person's state of health) Sickly, unhealthy, unwell.
  "Joe's in a bad way; he can't even get out of bed."
• (often childish) Not behaving; behaving badly; misbehaving; mischievous or disobedient.
  "Stop being bad, or you will get a spanking!"
• (sometimes childish) Evil; wicked.
  "Be careful. There are bad people in the world."
• (of food) Spoiled, rotten, overripe.
  "These apples have gone bad."

adj

• (informal, of a draft/check) Not covered by funds on account.
  "He gave me a bad check."

adj

• (semantic change, amelioration, contranymic) Good, superlative, excellent, cool.
  "Man, that new car you bought is bad!"
• (US) Overly promiscuous, licentious.
  "You leave your girl around me; if she's bad she's gonna get stuck."
• (originally African-American Vernacular, of a woman) Very attractive; hot, sexy.
  "Hopefully I can pull some bad bitches tonight."
• (Internet slang, sarcastic) Used without a copula to mock people who oppose something without having any real understanding of it.
  "Orange Man bad"

adv

• (now colloquial) Badly; poorly.
  "I didn't do too bad in the last exam."
• (intensifier) Badly; severely, extremely, passionately, eagerly.
  "I want you / I want you so bad, it's driving me mad"