lighterman vs tar

lighterman and tar both are nouns.

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

As nouns, tar is a hypernym of lighterman; that is, tar is a word with a broader meaning than lighterman:

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

lighterman (noun)	tar (noun)
someone who operates a barge	a man who serves as a sailor
	any of various dark heavy viscid substances obtained as a residue

lighterman (verb)	tar (verb)
	coat with tar