flora vs houseplant

flora and houseplant both are nouns.

Word	Noun	Adjective	Verb	Adverb
flora	Yes	No	No	No
houseplant	Yes	No	No	No

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

flora: (botany) a living organism lacking the power of locomotion
houseplant: any of a variety of plants grown indoors for decorative purposes

flora (noun)	houseplant (noun)
(botany) a living organism lacking the power of locomotion	any of a variety of plants grown indoors for decorative purposes
all the plant life in a particular region or period