noun

• (Australia) Any of various freshwater crayfish, typically of the genus Cherax, valued as food, especially Cherax destructor of southeastern Australia.
  "Having arrived at night I can speak with some authority on the desolate feeling the road produces: the white fire-scarred trunks, the unsettling vision of yabbies moving from one side of the road to the other."
• (Australia, chiefly Queensland) A species of marine ghost shrimp, Trypaea australiensis, widely harvested by recreational anglers as bait; a nipper.
  "Callianassa australiensis is known in southern New South Wales as the "ghost-nipper" (Dakin, Bennett and Pope, 1952), and in northern New South Wales and Queensland as the "yabby" (a word of aboriginal origin also applied to freshwater crayfish)."

verb

• (intransitive) To search, forage, or fish for yabbies.
  "He would have known the Merri well, given the affinity between boys and creeks, and he probably fished and yabbied there."

verb

• (transitive, Nigeria, slang) To show disrespect by denouncing or insulting; to diss.
  "So Abiola invite Fela to his house for a big party, and Fela have to go as they are family—even though Fela had yabbied Abiola in his song "ITT" [International Thief Thief]. And it's true, Abiola duped the country for that money—everybody knows it."