To be intoxicated by the consumption of yams; a condition that is common during the holiday seasons. Leads to odd family moments and lame jokes.
1. "These sweet potatoes are amazing!"
"Are you kidding? These are yams, sweet potatoes don't even fall into the Dioscoreaceae family. You're so yammered."
2. "Man, I want to go out and get yammered tonight at my parent's place. You up for it?"