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ayo m. (Noun) "tutor"
11th cent. From Latin avus "grandfather." From Proto-Italic *awo- 'id.' From Proto-Indo-European *h2eu̯h2- "grandparent."
Indo-European
Romance
Portuguese avô, Galician avó, Catalan avi, Occitan ièr, Italian avo, Dalmation jere, Romanian auș, Sardinian abu
Celtic
Old Irish aue "grandson," Middle Welsh ewythr "uncle," Middle Breton eontr 'id.'
Germanic
Gothic awo "grandmother," Old Norse ái "great-grandparent"
Albanian
Albanian dje
Balto-Slavic
Old Church Slavonic ujь, Old Prussian awis "uncle," Lithuanian avýnas "maternal uncle"
Armenian
Armenian haw

In the feminine, Latin avia "grandmother" took a different sense. See aya.