noun. The membranous outer covering of an organ or a blood vessel.

noun. In anatomy, any membranous structure covering an organ but not properly belonging to it (in full, membrana adventitia, adventitious membrane); specifically, the outermost of the three coats of a blood-vessel (in full, tunica adventitia, adventitious tunic), consisting of connective tissue.

noun. the membranous outer covering of an organ or blood vessel.

noun. The outermost layer of epithelial tissue encasing a visceral organ.

noun. an enveloping or covering membrane or layer of body tissue

"Figure 5.2 Moving Through The artery has three layers—the inner to help blood move through the artery (intima), the outer (adventitia) to protect it from the outside, plus a middle, muscular layer (media)."

adventitia bona  adventitious  tunica adventitia  

membrane  tissue layer  

albuginea  

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