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abuelo (Noun) "grandparent"
11th cent. Old Spanish abolo. First attestation of abuela is 13th cent. From Vulgar Latin *aviolus "grandfather" (lit. "little grandfather"), from Latin avus "grandfather" (see ayo and aya) and diminutive suffix -olus (see -uelo).
Indo-European
Romance
Asturian güelu, French aïeul
Basque
Basque agure "old man," borrowed from Vulgar Latin