Saint-John's-wort

noun

variants or Saint John's wort or St. 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

Illustration of Saint-John's-wort

Illustration of saint-john's-wort
  • Saint-John's-wort 1

Word History

Etymology

St. John the Baptist

First Known Use

15th century, in the meaning defined at sense 1

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

Dictionary Entries Near Saint-John's-wort

Cite this Entry

“Saint-John's-wort.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Saint-John%27s-wort. Accessed 21 Jul. 2024.

Medical Definition

Saint-John's-wort

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