Great technical term...
Heh, isn't it? I know a guy, a really crusty, crittery guy, and he always makes up words like that.
He uses "flattenicated" almost exclusively to describe animals in the road, as in "I saw a squirrel get flattenicated yesterday..." or "I saw a flattenicated raccoon today..."
Or sometimes to describe the results of some mishap as in "I dropped the screwdriver on the circuit board by accident, and it flattenicated the resistor..."