Main Entry: coc·cyx

Pronunciation: \ˈkäk-siks\

Function: noun

Inflected Form(s): plural coc·cy·ges \ˈkäk-sə-ˌjēz\ also coc·cyx·es \ˈkäk-sik-səz\

Etymology: New Latin, from Greek kokkyx cuckoo, coccyx; from its resemblance to a cuckoo's beak

Date: 1615

: a small bone that articulates with the sacrum and that usually consists of four fused vertebrae which form the terminus of the spinal column in humans and tailless apes