Jack vs tar

Jack and tar both are nouns.

Word	Noun	Adjective	Verb	Adverb
Jack	Yes	No	No	No
tar	Yes	No	Yes	No

As nouns, Jack and tar are synonyms defined as:

Other synonyms of Jack include gob, Jack-tar, mariner, old salt, sea dog, seafarer, seaman.

Jack (noun)	tar (noun)
a man who serves as a sailor	a man who serves as a sailor
	any of various dark heavy viscid substances obtained as a residue

Jack (verb)	tar (verb)
	coat with tar