Hands Down, Ass Up (noun, verb).
Noun: Refers to the squatting spread eagle position where your hands are planted firmly on the ground supporting the rest of your body, and your knees are used to prop your ass up in the air.
Verb: Refers to using the previously described position to perform a task or solve any of a wide variety of problems.
Noun Usage: While skiing, Jen fell into the HDAU position. Then righted herself.
Noun 2nd Definition: Hot Donna, Ass Up
Verb Usage: Don't know what to do? When in doubt, HDAU!