theanine
noun
the·a·nine
ˈthē-ə-ˌnēn 
variants
or L-theanine
: an amino acid C7H14N2O3 found especially in green tea and used as a dietary supplement
Green tea, which is rich in a depression-fighting amino acid called theanine, has previously been lauded for its health benefits.—
Camilla Turner
Camilla TurnerExamples of theanine in a Sentence
Recent Examples on the Web
Also, consider mixing magnesium with L-theanine, which can help calm you down even more.
—Sohaib Imtiaz, Verywell Health, 27 Oct. 2025
In addition to containing much less caffeine than coffee, black tea provides L-theanine, which has a calming effect on the body.
—Jillian Kubala, Health, 22 Oct. 2025
This gluten-free, dairy-free, vegan tablet is also supercharged with L-theanine, another stress-balancing adaptogen, for total relaxation amidst the most turbulent of days.
—Brianna Peters, Vogue, 10 Oct. 2025
Manage Your Stress Ashwagandha, St. John’s Wort, melatonin, theanine, and magnesium are commonly used to manage stress levels, as well as decrease anxiety and depression.
—Allison Futterman, Discover Magazine, 13 Feb. 2025
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Sohaib Imtiaz, Verywell Health, 27 Oct. 2025
In addition to containing much less caffeine than coffee, black tea provides L-theanine, which has a calming effect on the body.
—Jillian Kubala, Health, 22 Oct. 2025
This gluten-free, dairy-free, vegan tablet is also supercharged with L-theanine, another stress-balancing adaptogen, for total relaxation amidst the most turbulent of days.
—Brianna Peters, Vogue, 10 Oct. 2025
Manage Your Stress Ashwagandha, St. John’s Wort, melatonin, theanine, and magnesium are commonly used to manage stress levels, as well as decrease anxiety and depression.
—Allison Futterman, Discover Magazine, 13 Feb. 2025
See All Example Sentences for theanine
Cite this Entry
“Theanine.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/theanine. Accessed 30 Oct. 2025.
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