Deel is a multi contextual word much like
Jank, its mostly used as a sentence flavor booster, or a ice breaker usually getting a cheerful response or a questionable look when
said. Can be randomly
said at random times extremely loud just to say it without a reaction from anybody.
Tom - did you see what
harry was doing last
night, bob - no I didn't, harry - DEEL
Jason - Dude whats going on around here Moe - DEEL