noun

• (uncountable) The meat of this crustacean, served as food; crabmeat.
  "But Richmond[…]appeared to lose himself in his own reflections. Some pickled crab, which he had not touched, had been removed with a damson pie; and his sister saw[…]that he had eaten no more than a spoonful of that either."
• (in plural crabs, informal) An infestation of pubic lice (Pthirus pubis).
  "Although crabs themselves are an easily treated inconvenience, the patient and his partner(s) clearly run major STD risks."
• (uncountable, aviation) The angle by which an aircraft's nose is pointed upwind of its groundtrack to compensate for crosswinds during an approach to landing; its crab angle.
  "The pilot had to hold fifteen degrees of crab during the approach to keep her plane from getting blown off the localizer course."
• (poker slang) A playing card with the rank of three.

verb

• (intransitive) To fish for crabs.
• (transitive, US, slang) To ruin.
  "I thought at the time that that little speech meant a savin' of eight dollars,[…] But the Missus crabbed it a few minutes after her and Bess come in the room."
• (intransitive) To complain.
  "“The thing to do is to forget about the heat,” said Tom impatiently. “You make it ten times worse by crabbing about it.”"
• (transitive) To complain about.
  "Well, because of this state of things they crabbed his scheme from the first, ridiculed it, wrote against it, spread broadcast a feeling of distrust."

verb

• (obsolete) To irritate, make surly or sour
• (British dialect) To cudgel or beat, as with a crabstick
  "Get you to bed, drab, courage Or l'll so crab your shoulders!"
• (obsolete, transitive) To offend or insult.
  "If I think one thing and speak another, / I will both crab Christ and our Ladie His mother."

noun

• (informal) Clipping of carabiner, modified based on likening the shape of a carabiner to a crab's claw.