lamp vs furniture

lamp and furniture both are nouns.

Word	Noun	Adjective	Verb	Adverb
lamp	Yes	No	No	No
furniture	Yes	No	No	No

As nouns, furniture is a hypernym of lamp; that is, furniture is a word with a broader meaning than lamp:

Other hypernyms of lamp include article of furniture, piece of furniture.

lamp (noun)	furniture (noun)
an artificial source of visible illumination	furnishings that make a room or other area ready for occupancy
a piece of furniture holding one or more electric light bulbs