ophthalmic vein opht·hal·mic·vein uncommon noun 1. either of two veins that serve the eye; empties into the cavernous sinus Synonymsophthalmic veinvena ophthalmica Related words Broader terms vein Narrower terms inferior ophthalmic veinsuperior ophthalmic vein WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.