E. Rossoni notes that the term camillero designated in Sicily both the bearers of litters and the Camillian friars, that is, religious dedicated by vocation to the care of the sick. According to this author, the surname could indicate that the founder of the lineage had a relation with some convent of that order or practised the trade of litter-bearer. Its presence is documented mainly in the Caltanissetta, Agrigento and Palermo areas, with the variant Camillieri in the Ragusa area.

V. Blunda proposes a different etymology: the surname would derive from the Sicilian dialectal word camillèri, meaning "camel driver" or driver of camels. Blunda expressly rejects the popular interpretation that links it to the proper name Camillo, describing it as a false etymology. The surname would recall, instead, the introduction of the camel in Sicily during the Arab domination (9th–11th centuries), an animal used as a beast of burden in arid areas of the interior of the island, particularly around Agrigento and Caltanissetta, a practice documented until the late Middle Ages.