syphilis (n.)

infectious venereal disease, 1718, Modern Latin, originally from the title of a poem, "Syphilis, sive Morbus Gallicus" "Syphilis, or the French Disease," published 1530, by Veronese doctor Girolamo Fracastoro (1483-1553), which tells the tale of the shepherd Syphilus, supposed to be the first sufferer from the disease. Fracastoro first used the word as a generic term for the disease in his 1546 treatise "De Contagione."

Why he chose the name and what it meant to him are unknown; it may be intended as Latinized Greek for "Pig-lover" (with Latin sus "pig"). That and derivation from syn- "with" + philos "loving" form "the usual conjectures" [Century Dictionary], but there was as well a Sipylus, a son of Niobe, in Ovid.