— coccygeal /kok sij"ee euhl/ , adj.
/kok"siks/ , n. , pl. coccyges /kok suy"jeez, kok"si jeez'/ .
1. a small triangular bone forming the lower extremity of the spinal column in humans, consisting of four ankylosed rudimentary vertebrae. See diag. under spinal column .
2. a corresponding part in certain animals.
[ 1605-15; kókkyx cuckoo, from its resemblance to a cuckoo's beak ]