poop2 [intransitive] American English informal
poop outphrasal verb
to stop trying to do something because you are tired, bored etc:
Dan pooped out about halfway through the race.
to decide not to do something you have already said you would do, because you are tired or not interested
poop out on
'Is Bill coming along?' 'Nah, he's pooping out on us.'
if a machine or piece of equipment poops out, it stops working:
The laptop's battery pooped out after only two hours.