sue vs litigate

sue and litigate both are verbs.

Word	Noun	Adjective	Verb	Adverb
sue	No	No	Yes	No
litigate	No	No	Yes	No

As verbs, sue and litigate are synonyms defined as:

sue and litigate: institute legal proceedings against; file a suit against

Other synonyms of sue include action, process.

sue (verb)	litigate (verb)
institute legal proceedings against; file a suit against	institute legal proceedings against; file a suit against
	engage in legal proceedings