1928, from vasopressor "causing the constriction of (blood) vessels) (from vaso-, combining form of Latin vas "container, vessel;" see vas) + -in (2).
Entries linking to vasopressin
vas n.
in anatomy, "a tube, duct, or conduit for conveying blood, lymph, semen, etc.," plural vasa, Latin, literally "vessel." Vas deferens (plural vasa defferentia) is from 1570s.
-in 2
word-forming element in chemistry, usually indicating a neutral substance, antibiotic, vitamin, or hormone; a modification and specialized use of -ine (2).