What does "coccyx" mean?

The final (bottom-most) fused vertebrae at the base of the spine, the tailbone.

What is a synonym for "coccyx"?

Common synonyms include: bone, tail bone, tailbone, tailbone.

//ˈkɑksɪks// noun

noun ·Rare ·Advanced level

Noun

1
The final (bottom-most) fused vertebrae at the base of the spine, the tailbone. formal
"He lands on the concrete path and bounces on his coccyx, which cracks the base of his spine."
2
the end of the vertebral column in humans and tailless apes wordnet

"The coccyx is a vestigial feature that shows the common ancestry of mankind and apes."

From Latin coccyx, from Ancient Greek κόκκυξ (kókkux, “cuckoo”), referring to the curved shape of a cuckoo's beak when viewed from the side.

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.