interjection/ˈiʝo/
used to address a child; hey kid!; used to address one's friends; mate; dude; my guy; interjection to express excitement, surprise, annoyance, etc.; oh dude!; used to get someone's attention; hey you!
A shortened form of quillo (a term of endearment for a young person used in Andalusia), itself a shortened form of chiquillo, a diminutive of chico (“kid”).