May blob vs marsh plant

May blob and marsh plant both are nouns.

Word	Noun	Adjective	Verb	Adverb
May blob	Yes	No	No	No
marsh plant	Yes	No	No	No

As nouns, marsh plant is a hypernym of May blob; that is, marsh plant is a word with a broader meaning than May blob:

May blob: swamp plant of Europe and North America having bright yellow flowers resembling buttercups
marsh plant: a semiaquatic plant that grows in soft wet land; most are monocots: sedge, sphagnum, grasses, cattails, etc; possibly heath

Other hypernyms of May blob include bog plant, swamp plant.

May blob (noun)	marsh plant (noun)
swamp plant of Europe and North America having bright yellow flowers resembling buttercups	a semiaquatic plant that grows in soft wet land; most are monocots: sedge, sphagnum, grasses, cattails, etc; possibly heath