Drunk or completely shitfaced. When you don't want to use shitfaced so you use duckfaced cos it's more appropriate for family audience so they don't know wtf you're talking about.
A person whose Facebook pictures are almost exclusively of themselves and/or their friends making the duck face. This behavior is often seen with teenage or college-aged girls, or drunk women. Also often accompanied by pictures of other acts, such as making wannabe gang signs with their hands.
Guy 1: "Man, her Facebook pictures are nothing but her and her drunk friends making those stupid kissy faces."
Guy 2: "Dude, you've just seen her duckfacebook."
Guy 1: "That sucks, but I'd still hit that shit."
In basketball, dunking in the face of an opposing player; a posterization. generally entails an aggressive or acrobatic dunk or move to the basket. Popularized by the ESPN show "SportsNation"