In Vietnamese it means "Satan" or "Devil" or "Lord of the Underworld" or perhaps "Ghost"? It can be used as a singular or in conjunction with other phrases or words.
Con me may. Di o voi ong ma quy di! - Mother fucker (Yo mama). Why don't you go to hell or go live with Satan/Devil!
Ong ma quy! - A ghost!
Ong ma quy! - A ghost!
by Angry Gook September 5, 2012
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