gas plant vs herbaceous plant

gas plant and herbaceous plant both are nouns.

Word	Noun	Adjective	Verb	Adverb
gas plant	Yes	No	No	No
herbaceous plant	Yes	No	No	No

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

gas plant: Eurasian perennial herb with white flowers that emit flammable vapor in hot weather
herbaceous plant: a plant lacking a permanent woody stem; many are flowering garden plants or potherbs; some having medicinal properties; some are pests

Other hypernyms of gas plant include herb.

gas plant (noun)	herbaceous plant (noun)
Eurasian perennial herb with white flowers that emit flammable vapor in hot weather	a plant lacking a permanent woody stem; many are flowering garden plants or potherbs; some having medicinal properties; some are pests