fishgig vs harpoon

fishgig and harpoon both are nouns.

Word	Noun	Adjective	Verb	Adverb
fishgig	Yes	No	No	No
harpoon	Yes	No	Yes	No

As nouns, harpoon is a hyponym of fishgig; that is, harpoon is a word with a more specific, narrower meaning than fishgig:

fishgig: an implement with a shaft and barbed point used for catching fish
harpoon: a spear with a shaft and barbed point for throwing; used for catching large fish or whales; a strong line is attached to it

Other hyponyms of fishgig include leister.

fishgig (noun)	harpoon (noun)
an implement with a shaft and barbed point used for catching fish	a spear with a shaft and barbed point for throwing; used for catching large fish or whales; a strong line is attached to it

fishgig (verb)	harpoon (verb)
	spear with a harpoon