milk thistle

noun

: a tall thistle (Silybum marianum) having white-veined dark green leaves and large purple flower heads that is native to the Mediterranean region but has become naturalized elsewhere including the U.S.
also : an extract of milk thistle and especially its seeds that is held to protect the liver from damage or disease

Examples of milk thistle in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The milk thistle extract and alpha lipoic acid could make the supplement more effective. — Bestreviews, Chicago Tribune, 29 Jan. 2026 Despite its claims, there’s no evidence to prove that milk thistle supplements can prevent a hangover. — Nick Blackmer, Verywell Health, 23 Sep. 2025 Like daikons and comfrey, milk thistle’s long, penetrating roots draw nutrients up from deep in the soil and aerate dense garden beds. — Lauren Landers, Better Homes & Gardens, 14 Apr. 2026 And milk thistle—which is more supplement than supermarket staple—has mixed evidence on its effects on liver enzyme levels. — Francesca Krempa, Bon Appetit Magazine, 12 Dec. 2025 See All Example Sentences for milk thistle

Word History

First Known Use

1562, in the meaning defined above

Time Traveler
The first known use of milk thistle was in 1562

Rhymes for milk thistle

See All Rhymes for milk thistle

Browse Nearby Words

milk sugar
milk thistle
milk toast
See all Nearby Words

Cite this Entry

“Milk thistle.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/milk%20thistle. Accessed 8 Jul. 2026.

Copy Citation

Medical Definition

milk thistle

noun
milk this·​tle -ˈthis-əl How to pronounce milk thistle (audio)
1
: a tall thistle (Silybum marianum) that is the source of silymarin, has large clasping white-blotched leaves and large purple flower heads with bristly receptacles, and is native to southern Europe but has been widely introduced elsewhere including the United States
2
: an extract of milk thistle and especially its seeds : silymarin
Last Updated: - Updated example sentences
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