1. The act of denying someone your leftover food.
2. Refusing to share your food with someone even though you aren't going to eat it and plan on throwing it away.
Person 1 - Hey man, are you gonna finish that?
Person 2 - No, but you can't have it cuz you've already eaten enough food to feed 3 people. You are cut off!
Person 1 - You are such a food block...
Dude, I'm so hungry! Stop food blocking me and let me eat your leftover food!