Where does “arriedro” come from?

arriedro (Old Spanish) comes from Vulgar Latin ad retro, from Latin Ad, from Latin illic, from Latin ille, from Latin olle, from Proto-Italic *olnos — that.

Ancestry of “arriedro”, step by step

Step	Language	Word	Meaning
1	Vulgar Latin	ad retro	to the rear
2	Latin	Ad	toward, to
3	Latin	illic	he, she, it, yonder, that, overthere; in that...
4	Latin	ille	that; those; "; demonstrative pronoun "; that...
5	Latin	olle	Archaic form of ille
6	Proto-Italic	*olnos	that

Words derived from “arriedro”

arredro
arredrar

Every word from Proto-Italic *olnos →Every word from Latin olle →Every word from Latin ille →