Jack-tar vs tar

Jack-tar and tar both are nouns.

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

As nouns, Jack-tar and tar are synonyms defined as:

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

Jack-tar (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-tar (verb)	tar (verb)
	coat with tar