The hamate bone or unciform bone (from Latin uncus, "hook") is a bone in the human wrist readily distinguishable by its wedge shape and a hook-like process ("hamulus") projecting from its palmar surface.

The hamate is an irregularly shaped carpal bone found within the hand. The hamate is found within the distal row of carpal bones, and abuts the metacarpals of the little finger and ring finger.

The carpal bones function as a unit to provide a bony superstructure for the hand.

The bone is also found in many other mammals, and is homologous with the "fourth distal carpal" of reptiles and amphibians.

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