Synonyms

coccyx

American

[kok-siks] / ˈkɒk sɪks /

noun

a small triangular bone forming the lower extremity of the spinal column in humans, consisting of four ankylosed rudimentary vertebrae.
a corresponding part in certain animals.

coccyx British

/ kɒkˈsɪdʒɪəl, ˈkɒksɪks /

noun

a small triangular bone at the end of the spinal column in man and some apes, representing a vestigial tail

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

coccyx Scientific

/ kŏk′sĭks /

A small triangular bone at the base of the spine in humans and apes. It is composed of several fused vertebrae.
Also called tailbone

Other Word Forms

Derived Forms

Inflected Forms

noun

coccyges

plural

Etymology

Origin of coccyx

1605–15; < New Latin < Greek kókkyx cuckoo, from its resemblance to a cuckoo's beak

Compare meaning

How does coccyx compare to similar and commonly confused words? Explore the most common comparisons:

sacrum vs. coccyx

Vocabulary lists containing coccyx

Human Anatomy and Physiology - High School

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The COCCYX, in infants, consists of several pieces, which, in youth, become united and form one bone.

From A Treatise on Anatomy, Physiology, and Hygiene (Revised Edition) by Cutter, Calvin

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023