The authors agree that the surname is of Greek origin and derives from the term agelàios, meaning "wild, untamed, belonging to the herd".

E. Rossoni derives it from a nickname based on the Greek term agelàios ("wild, untamed"), which also gave rise to the name Agelàios.

V. Blunda, for the Sicilian variant, derives it from the etymon Agelàios ("wild, belonging to the herd"). He notes that the root goes back to agèle ("flock, herd") and described both undomesticated animals and people of a rough or solitary character. He adds that the surname was incorporated into the Sicilian onomastic stock as a descriptive nickname in a society where livestock and pastoralism were fundamental activities of the rural landscape.