ret·​i·​nac·​u·​lum ˌre-tə-ˈna-kyə-ləm How to pronounce retinaculum (audio)
plural retinacula ˌre-tə-ˈna-kyə-lə How to pronounce retinaculum (audio)
: any of several fibrous bands of fascia that pass over or under tendons (as at or near the ankle or wrist) and help to keep them in place

Example Sentences

Recent Examples on the Web The carpal tunnel is a literal tunnel of space bordered by the carpal (wrist) bones and their ligaments, and by a connective tissue structure called the flexor retinaculum. Dr. Keith Roach, oregonlive, 10 May 2022 The compression is alleviated by surgical release of the retinaculum, which gives the nerve adequate room. Dr. Keith Roach, oregonlive, 10 May 2022

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'retinaculum.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


borrowed from New Latin retināculum, going back to Latin, "rope holding something in place, cable, hawser," from retinēre "to hold fast, detain, keep possession of" + -ā-, stem formative of verbs + -culum, suffix of instrument and place (going back to Indo-European *-tlom), probably after gubernāculum "steering oar of a ship" (from gubernāre "to steer") or other derivatives of 1st-conjugation verbs — more at retain

First Known Use

circa 1825, in the meaning defined above

Time Traveler
The first known use of retinaculum was circa 1825

Dictionary Entries Near retinaculum

Cite this Entry

“Retinaculum.” Dictionary, Merriam-Webster, Accessed 28 May. 2023.

Medical Definition


ret·​i·​nac·​u·​lum -ləm How to pronounce retinaculum (audio)
plural retinacula -lə How to pronounce retinaculum (audio)

More from Merriam-Webster on retinaculum

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