RichThesaurus
crap one's pants
vs
split one's sides
crap one's pants
verb
To be extremely frightened.
To defecate into one's pants or other clothing.
split one's sides
verb
To laugh hysterically.
How often have the words
crap one's pants
and
split one's sides
occurred in a corpus of books?
(source:
Google Ngram Viewer
)