ad·​ven·​ti·​tia | \ ˌad-vən-ˈti-shə How to pronounce adventitia (audio) , -(ˌ)ven- \

Definition of adventitia

: an external chiefly connective tissue covering of an organ especially : the external coat of a blood vessel

Other Words from adventitia

adventitial \ ˌad-​vən-​ˈti-​shəl How to pronounce adventitial (audio) , -​(ˌ)ven-​ \ adjective

First Known Use of adventitia

1854, in the meaning defined above

History and Etymology for adventitia

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

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The first known use of adventitia was in 1854

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Cite this Entry

“Adventitia.” Dictionary, Merriam-Webster, Accessed 5 Jul. 2020.

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ad·​ven·​ti·​tia | \ ˌad-vən-ˈtish-(ē-)ə How to pronounce adventitia (audio) , -(ˌ)ven- How to pronounce adventitia (audio) \

Medical Definition of adventitia

: 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

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