Spanish word abuelo comes from Latin -olus, Latin avus (An ancestor. An old man. Grandfather.)
-olus (Latin)
avus (Latin)
An ancestor. An old man. Grandfather.
*aviolus (Latin)
(Vulgar Latin) grandfather.
abuelo (Spanish)
(colloquial, affectionate) an elderly person. Grandfather. Loose tufts of hair in the nape when one's hair is messed up.