This is a mash up of “get your act/shit together” (get organized) and “get off your ass” (stop loafing and get to work). Both idioms direct someone to get moving, invoking a congruent conflation. Also ass and act are three letter words that have a similar sound. Finally, the lower half of the body is at work here in both phrases. Many thanks to Robyn Pietrucha for blurting this one out and passing it along!
This is a mash up of “cover his butt (ass)” (make excuses or otherwise take action to avoid being blamed) and “don’t stick your neck out” (avoid risk). This malaphor was said by a person describing his physician and the excessive treatment given. I think it also applies to Congress lately…. A tip of the hat to JoErin O’Leary for sending this one in!
I won’t reveal the source, but this is a mash up of “you’ve got a chip on your shoulder” (bad attitude) and “you’ve got a stick up your ass” (up tight). It also could describe the aftermath of gorging on a bag of Cape Cod potato chips in your underwear (never done that, just sayin’).