(informal) Something off-putting or suspicious is in the air.

(informal) The reasonable, but possibly incorrect, motivations or premises to someone's argument.

To attract or appeal to someone.

(US, informal) What is wrong with X? What's X's problem? Is X crazy?

(UK, slang, archaic) To scupper someone's plans.

(slang, dated) To make someone angry.

(American spelling) Alternative form of someone's arse off.

(reflexive) With great effort, vigour or gusto, or to the point of excess. / (reflexive) Used as a general negative intensifier: to an extreme degree.

Used to say that someone or something deserves praise and applause.

(informal) To be romantically or sexually involved with someone.