"boy used in pederasty," 1590s, from Latin Catamitus, corruption of Ganymedes, the name of the beloved cup-bearer of Jupiter (see Ganymede). Cicero used it as a contemptuous insult against Antonius.
Entries linking to catamite
Ganymede
Trojan youth taken by Zeus as his cup-bearer (and lover), from Greek Ganymedes, perhaps a non-Greek name, or from ganymai "I rejoice, am glad" (related to ganos "brightness; sheen; gladness, joy; pride") + medea (plural) "counsels, plans, cunning" (see Medea); taken in Greek folk-etymology to mean "delighting in genitals."
Used figuratively of serving-boys (c. 1600) and catamites (1590s). Associated with Aquarius in the zodiac. As the name of one of the four large satellites of Jupiter, proposed in Latin 1610s, but not widely used before 1847.