lantern vs dark lantern

lantern and dark lantern both are nouns.

Word	Noun	Adjective	Verb	Adverb
lantern	Yes	No	No	No
dark lantern	Yes	No	No	No

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

lantern: light in a transparent protective case
dark lantern: a lantern with a single opening and a sliding panel that can be closed to conceal the light

Other hyponyms of lantern include Chinese lantern, bull's-eye, jack-o'-lantern.

lantern (noun)	dark lantern (noun)
light in a transparent protective case	a lantern with a single opening and a sliding panel that can be closed to conceal the light