it's a greeting word. similar to hey, what's going on
Renz: What's the deelio
Jam: Oh just chilling
Similar to whats up or whats really good. Meaning whats goining on or whats poppin
Seattle version of deely, an object or thing you can't remember the the word for or are too lazy to even try to remember it.
I wanted to ride my scooter for coffee, but I can't find my "deelio". referring to my helmet.