n. the result of defecating with violent intensity
a. resembling the result of violent defecation
Pewp is a more intense version of poop, with the change in spelling meant to suggest violence (i.e. "Pew-pew-pew!", as if feces is being launched from, rather than squeezed out of, the anus.)
Pull over at the next rest stop, man! I gotta pewp so hard I'm liable to shatter a toilet bowl!
When someone swallows several vials of food coloring, thus producing a multi colored poop smelling of fresh lavender, wheat grains and eroded soil from a grave with a person by the name of Jack on a tombstone.