adventitia

noun

ad·​ven·​ti·​tia ˌad-vən-ˈti-shə How to pronounce adventitia (audio)
-(ˌ)ven-
: an external chiefly connective tissue covering of an organ
especially : the external coat of a blood vessel
adventitial
ˌad-vən-ˈti-shəl How to pronounce adventitia (audio)
-(ˌ)ven-
adjective

Word History

Etymology

borrowed from New Latin, alteration of Latin adventīcia, neuter plural of adventīcius "coming from outside, external" — more at adventitious

First Known Use

1854, in the meaning defined above

Time Traveler
The first known use of adventitia was in 1854

Dictionary Entries Near adventitia

Adventism

adventitia

adventitial cell

See More Nearby Entries 

Cite this Entry

“Adventitia.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/adventitia. Accessed 22 Nov. 2024.

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Medical Definition

adventitia

noun
ad·​ven·​ti·​tia ˌad-vən-ˈtish-(ē-)ə How to pronounce adventitia (audio) -(ˌ)ven- How to pronounce adventitia (audio)
: the outer layer that makes up a tubular organ or structure and especially a blood vessel, is composed of collagenous and elastic fibers, and is not covered with peritoneum

called also tunica adventitia, tunica externa

More from Merriam-Webster on adventitia

Britannica.com: Encyclopedia article about adventitia

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