an exclamation. it usually has no meaning, it is just a word to use when you're bored or you're feeling crazy or you think the room you're in is too quiet.
weeee! waaaaa! woooo! I love Dave Davies! Ooky-ooky!
A small plastic horse toy with wheels popular in the 1960's. Child's ride-on toy. Ooky-Ookies came in several different colors and were hollow, with handles sticking out of the horse's head.
Emily went out to ride her Ooky-Ooky.