mahogany vs brownness

mahogany and brownness both are nouns.

Word	Noun	Adjective	Verb	Adverb
mahogany	Yes	No	No	No
brownness	Yes	No	No	No

As nouns, brownness is a hypernym of mahogany; that is, brownness is a word with a broader meaning than mahogany:

Other hypernyms of mahogany include brown.

mahogany (noun)	brownness (noun)
a shade of brown with a tinge of red	an orange of low brightness and saturation
any of various tropical timber trees of the family Meliaceae especially the genus Swietinia valued for their hard yellowish- to reddish-brown wood that is readily worked and takes a high polish
wood of any of various mahogany trees; much used for cabinetwork and furniture