Wiktionary
take a shit
vb. 1 (context idiomatic vulgar colloquial English) To defecate. 2 (context idiomatic vulgar colloquial UK English) To fail or malfunction.
WordNet
Usage examples of "take a shit".
Phil, who was watching Roslyn take a shit in the food-trough, said: 'Speak for yourself.
You're no more free to run off and marry some little slut you've been screwing between the filing cabinets than the president is to take a shit on the White House lawn!
Somebody says that is because when they is out in the desert an gotta take a shit, they can grap ahold of the ends of the shoes when they bend over an it keeps them on balance.