Half-Cog

Adj. Someone who is dim-witted, especially from New England. Short for "Half-Cognitive".
Half-Cogs are so incredibly stupid, they can only relate to other Half-Cogs for any form of reasoning.

Jim: "That guy over there has been trying to put his shoes on for like 15 minutes..."

Todd: "Dude, he's wearing sandals..."

Jim: "That's what I'm saying. He's a total Half-Cog!"