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-uelo, -elo, -illo, -iello, -el Diminutive suffix.

From Latin -olus, -ellus, -illus, -lus 'id.' All from original Latin suffix -ulus 'id.' The vowel changes and consonant additions were due to sound conditioning. From Proto-Italic *-elos. From Proto-Indo-European *-elo- 'id.'

Romance: Western Vulgar Latin: Asturian -uelu, Portuguese -ulo, Galician -ulo, Catalan -ul, French -ule, Italian -olo; Eastern Vulgar Latin: Romanian -ul

Italic: Oscan kaíla "sacred building" (kaχ-elā-), Faliscan cela "small storeroom" (kēl-elā-)

Indo-European: Celtic: Welsh -el, Breton -el; Germanic: Old Icelandic -ull, Old English -l, Old High German -ala,