n.
Pronunciation: ' käk-siks
Function: noun
Inflected Form: plural coc · cy · ges \ ' käk-s ə - ˌ j ē z \ also coc · cyx · es \ ' käk-sik-s ə z \
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