late 14c., "first tine or branch of the horns of a deer," from Anglo-French auntiler, Old French antoillier (14c., Modern French andouiller) "antler," which is perhaps from Gallo-Roman cornu *antoculare "horn in front of the eyes," from Latin ante "before" (from PIE root *ant- "front, forehead," with derivatives meaning "in front of, before") + ocularis "of the eyes" (from Latin oculus "an eye," from PIE root *okw- "to see").
This etymology is doubted by some because no similar word exists in any other Romance language, but compare German Augensprossen "antlers," literally "eye-sprouts," for a similar formation. Later used of any branch of the horns. Related: Antlered (1813).