E. Rossoni notes that this surname is very rare and peculiar to the Reggio Calabria area, and proposes two possible etymologies. The first links it to the Latin name Caecilia, a cognomen of the Gens Metilia, associated with Saint Cecilia, martyred in the year 232. The second, of a dialectal character, relates it to the word cilìa, which in the Greek dialect of the Bova area, in Calabria, means "belly", derived from the Greek καλία.

G. Rohlfs agrees on the Greek-Byzantine origin of the surname and on its presence in the Reggio Calabria area, with specific records in localities such as Montebello, Palmi and Siderno. Rohlfs also connects it with the Grecanic dialectal word cilìa ("belly"), although he specifies that the Greek etymon is κοιλία —instead of καλία as Rossoni indicates—, and adds that in Greece it survives as a surname under the form Kilias. He also considers that Cilea is a sibling form of Cilìa, and that the variant with an accent can lose it in migratory contexts.

As for the form Cilia —a closely related graphic variant—, Rossoni indicates that it is clearly Sicilian, spread throughout the island with greater concentration in the Ragusa area, and likewise associates it with the Latin name Caecilia.