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
Some supplements, such as melatonin, L-theanine, and tryptophan, may have an additive or synergistic effect on sleep when taken with magnesium.
—
Emmanuella Ogbonna,
Health,
17 June 2026
Common nootropics in mocktails include l-theanine, lion’s mane mushroom, lemon balm and ginkgo biloba.
—
Lauren Schuster,
Miami Herald,
27 May 2026
What's more, green tea contains L-theanine, a type of amino acid, per Allen.
—
Kirsten Nunez,
Martha Stewart,
12 May 2026
Each gummy contains a mild blend of melatonin, L-theanine and botanicals to be taken only occasionally when sleep is difficult.
—
Bestreviews,
Chicago Tribune,
8 May 2026
See All Example Sentences for theanine
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Emmanuella Ogbonna,
Health,
17 June 2026
Common nootropics in mocktails include l-theanine, lion’s mane mushroom, lemon balm and ginkgo biloba.
—
Lauren Schuster,
Miami Herald,
27 May 2026
What's more, green tea contains L-theanine, a type of amino acid, per Allen.
—
Kirsten Nunez,
Martha Stewart,
12 May 2026
Each gummy contains a mild blend of melatonin, L-theanine and botanicals to be taken only occasionally when sleep is difficult.
—
Bestreviews,
Chicago Tribune,
8 May 2026
See All Example Sentences for theanine
Cite this Entry
“Theanine.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/theanine. Accessed 26 Jun. 2026.
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