A term morons use, particularly when bad weather is afoot, to which they confuse the meaning of "hunker" with. Bunker is a noun, yet hunker is a verb, thus while the words sound similar, when thought of in their linguistic context, one is blatantly wrong.
The storms a comin' we needs to bunker down.
Term used by confused individuals, who are not sure if they want to hunker down or to go and get in a bunker.
Halo Player 1: F***! A tank with 2 ghosts iz at our base!
Moron: WTF! Oh crap! Bunker down!