Hypericum vs St John's wort

Hypericum and St John's wort both are nouns.

Word	Noun	Adjective	Verb	Adverb
Hypericum	Yes	No	No	No
St John's wort	Yes	No	No	No

Hypericum (noun)	St John's wort (noun)
large almost cosmopolitan genus of evergreen or deciduous shrubs and herbs with often showy yellow flowers; cosmopolitan except tropical lowlands and Arctic or high altitudes and desert regions	any of numerous plants of the genus Hypericum having yellow flowers and transparently dotted leaves; traditionally gathered on St John's eve to ward off evil