test case vs test suit

test case and test suit both are nouns.

Word	Noun	Adjective	Verb	Adverb
test case	Yes	No	No	No
test suit	Yes	No	No	No

As nouns, test case and test suit are synonyms defined as:

test case and test suit: a representative legal action whose outcome is likely to become a precedent

test case (noun)	test suit (noun)
a representative legal action whose outcome is likely to become a precedent	a representative legal action whose outcome is likely to become a precedent