pi·​lo·​ni·​dal ˌpī-lə-ˈnī-dᵊl How to pronounce pilonidal (audio)
: of, relating to, or being a hair-containing cyst of the skin in the lower-back region near the upper crease of the buttocks

Examples of pilonidal in a Sentence

Recent Examples on the Web Isabell suffers from pilonidal disease, a chronic skin infection that causes cysts to form in the crease between the buttocks. USA Today, 25 Feb. 2021

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

Word History


Latin pilus hair + nidus nest

First Known Use

1880, in the meaning defined above

Time Traveler
The first known use of pilonidal was in 1880

Dictionary Entries Near pilonidal

Cite this Entry

“Pilonidal.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pilonidal. Accessed 24 Jul. 2024.

Medical Definition


pi·​lo·​ni·​dal ˌpī-lə-ˈnīd-ᵊl How to pronounce pilonidal (audio)
: containing hair nested in a cyst
used of congenitally anomalous cysts in the sacrococcygeal area that often become infected and discharge through a channel near the anus
: of, relating to, involving, or for use on pilonidal cysts, tracts, or sinuses
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