Saint-John's-wort

noun

ˈsānt-ˈjänz-ˌwərt  -ˌwȯrt 

variants or Saint John's wort or St. John's wort

1

: any of a large genus (Hypericum of the family Hypericaceae, 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

Illustration of Saint-John's-wort

• Saint-John's-wort 1

Examples of Saint-John's-wort in a Sentence

Recent Examples on the Web

Saint-John's-Wort Saint-John's-wort is an herbal supplement known for its antidepressant effects. —Sohaib Imtiaz, Verywell Health, 17 Apr. 2025

Saint-John's-Wort Saint-John's-wort is an herbal dietary supplement that many people take for mild to moderate symptoms of depression, as well as various other conditions.13 Taking this supplement with Zoloft can increase the risk of serotonin syndrome. —Karen Berger, Pharmd, Verywell Health, 20 Feb. 2025

Saint-John's-wort is an herbal dietary supplement that many people take for mild to moderate symptoms of depression, as well as various other conditions.13 Taking this supplement with Zoloft can increase the risk of serotonin syndrome. —Karen Berger, Pharmd, Verywell Health, 20 Feb. 2025

Word History

Etymology

St. John the Baptist

First Known Use

15th century, in the meaning defined at sense 1

Medical Definition

Saint-John's-wort

noun

variants or Saint John's wort or St. John's wort

-ˈjänz-ˌwərt  -ˌwȯ(ə)rt 

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

: 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