Late 1970s term for a male dressed like a disco dancer.
It was mostly an insult but was sometimes used in jest or for an ego boost. Often yelled at a male with new disco-like clothes or a new haircut in the John Travolta style or a guy on the dance floor trying to emulate him.
Nice Travolta haircut Noah!...you trying to be Danny Disco?
Hey Danny Disco! Stop making moves on my girl!!
Watch-out guys--tonight I'm Danny Disco!!!