making water vs passing water

making water and passing water both are nouns.

Word	Noun	Adjective	Verb	Adverb
making water	Yes	No	No	No
passing water	Yes	No	No	No

As nouns, making water and passing water are synonyms defined as:

Other synonyms of making water include leak, wetting.

making water (noun)	passing water (noun)
a euphemism for urination	a euphemism for urination