Andalusia azagador (trashumance) "royal path for cattle," azagar "to drive cattle in a line," probably borrowed from Aragonese azagar
Aragonese azagar "to drive cattle in a line," Catalan assagador "farmer's path"
The word is not the origin of the surname Zaga. The surname, according to Tibón (1988), was originally given to Sephardic Jewish families and is of unknown origin. Tibón speculates the surname may derive as an apocopation of Zagarolo, name of a town near Rome, Italy.