noun

• (Commonwealth, now vulgar) The buttocks or more specifically, the anus.
  "As the novel progresses, he is shot in the hand with his own gun, shot in the arse with someone else's and lacerated by a prosthetic weed trimmer."
• (chiefly UK, Ireland, Commonwealth, derogatory, slang) A stupid, pompous, arrogant, mean or despicable person.
  "“You're an arse,” Ellen said. ¶ “Please? You must like something about me …?” ¶ “I do. You're an arse. I just told you that. I feel comfy with you, because you're such an arse.”"
• (vulgar, slang, uncountable) Used in similes to express something bad or unpleasant.
• (vulgar, slang, metonymic, countable) A person; the self; (reflexively) oneself or one's person, chiefly their body; (by extension) one's personal safety, or figuratively one's job, prospects, etc.

verb

• (Commonwealth, slang, intransitive) To be silly, act stupid or mess around.
  "Stop arsing around!"

intj

• (Commonwealth) An expression of frustration.
  "(euphemistic)"

noun

• (biochemistry) Abbreviation of arylsulfatase E, an enzyme, deficiencies in which are associated with abnormalities in cartilage and bone development.