Any of various deep-seated arteries and veins; especially a deep branch of the femoral artery and the accompanying vein.
Also in scientific Latin compounds forming the names of particular deep-seated arteries and veins, as profunda femoris, profunda brachii, etc..
Origin
Late Middle English; earliest use found in Guy de Chauliac's Grande Chirurgie. From post-classical Latin profunda, use as noun (short for vena profunda or arteria profunda) of classical Latin profunda, feminine singular of profundus.