Someone who has given head to someone, also can be used at "To Dack" which means give head. Usually used as an insult in the same way asshole is.
Example one:
Joe: do you think Jenny is a Dackface yet?
Alex: Nah probably not shes a prude
Example Two:

Avi: alex your such a fucking dackface sometimes
Alex "goes and crys in a corner"
by see'ee'es jay'dee'es June 4, 2010
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