Saint-John's-wort

noun
\ˈsānt-ˈjänz-ˌwərt, -ˌwȯrt\

Definition of Saint-John's-wort 

1 : any of a large genus (Hypericum of the family Guttiferae, the Saint-John's-wort family) of cosmopolitan herbs and shrubs with showy pentamerous yellow flowers

2 : the dried aerial parts of a Saint-John's-wort (Hypericum perforatum) that are held to relieve depression and are used in herbal remedies and dietary supplements

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Illustration of saint-john's-wort

Saint-John's-wort 1

First Known Use of Saint-John's-wort

15th century, in the meaning defined at sense 1

History and Etymology for Saint-John's-wort

St. John the Baptist

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The first known use of Saint-John's-wort was in the 15th century

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Saint-John's-wort

noun
\-ˈjänz-ˌwərt, -ˌwȯ(ə)rt \

Medical Definition of Saint-John's-wort 

1 : any of a genus (Hypericum of the family Guttiferae, the Saint-John's-wort family) of herbs and shrubs with showy yellow flowers especially : one (H. perforatum) of dry soil, roadsides, pastures, and ranges that contains a photodynamic pigment causing dermatitis due to photosensitization in sheep, cattle, horses, and goats when ingested — see hypericism

2 usually Saint John's wort : the dried aerial parts of a Saint-John's-wort (Hypericum perforatum) that are held to relieve depression and are used in herbal remedies and dietary supplements

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