flagroot vs swamp plant

flagroot and swamp plant both are nouns.

Word	Noun	Adjective	Verb	Adverb
flagroot	Yes	No	No	No
swamp plant	Yes	No	No	No

As nouns, swamp plant is a hypernym of flagroot; that is, swamp plant is a word with a broader meaning than flagroot:

flagroot: perennial marsh plant having swordlike leaves and aromatic roots
swamp plant: a semiaquatic plant that grows in soft wet land; most are monocots: sedge, sphagnum, grasses, cattails, etc; possibly heath

Other hypernyms of flagroot include bog plant, marsh plant.

flagroot (noun)	swamp plant (noun)
perennial marsh plant having swordlike leaves and aromatic roots	a semiaquatic plant that grows in soft wet land; most are monocots: sedge, sphagnum, grasses, cattails, etc; possibly heath