English word intravenous comes from English venous, English intra- (A prefix signifying inside, within, interior, during.)

Detailed word origin of intravenous

Dictionary entry	Language	Definition
venous	English (eng)	Having numerous veins.. Of or pertaining to veins.. Possessing veins.
intra-	English (eng)	A prefix signifying inside, within, interior, during.
intravenous	English (eng)	(medicine) A dose of medicine administered from a drip, down through a hollow needle inserted into a patient's vein. Inside the veins.

Words with the same origin as intravenous