coolwart vs herb

coolwart and herb both are nouns.

Word	Noun	Adjective	Verb	Adverb
coolwart	Yes	No	No	No
herb	Yes	No	No	No

As nouns, herb is a hypernym of coolwart; that is, herb is a word with a broader meaning than coolwart:

coolwart: stoloniferous white-flowered spring-blooming woodland plant
herb: a plant lacking a permanent woody stem; many are flowering garden plants or potherbs; some having medicinal properties; some are pests

Other hypernyms of coolwart include herbaceous plant.

coolwart (noun)	herb (noun)
stoloniferous white-flowered spring-blooming woodland plant	aromatic potherb used in cookery for its savory qualities
	a plant lacking a permanent woody stem; many are flowering garden plants or potherbs; some having medicinal properties; some are pests