the·​a·​nine ˈthē-ə-ˌnēn How to pronounce theanine (audio)
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

Examples of theanine in a Sentence

Recent Examples on the Web Green tea has the highest concentration of theanine compared to other types of tea, according to a 2016 study in Pharmacognosy Magazine. Lindsay Funston, Health, 12 Dec. 2022 In dog calming supplements, theanine is often included to enhance its anxiety-reducing properties. Amber Smith, Discover Magazine, 5 Aug. 2023 Matcha contains about 70 milligrams of caffeine per eight ounces, while a cup of coffee has about 90 milligrams of caffeine per 8 ounces; however, the caffeine in matcha is released more slowly and steadily due to L-theanine. L'oreal Thompson Payton, Fortune, 12 Feb. 2023 Long, strong focus and concentration from Vyvamind’s clever caffeine + L-theanine stack. Dallas News, 23 Aug. 2022 Related Story Caffeine Lovers Swear By Coffee Subscription Boxes Matcha contains an amino acid called l-theanine, which helps your body absorb the caffeine more slowly, says Gans. Jackie Lam, Women's Health, 24 Feb. 2023 This sophisticated formula contains pure caffeine from organic green tea extract and theanine to help increase alertness, as well as beta alanine and citrulline malate for improved endurance and power output. Amber Smith, Discover Magazine, 6 Feb. 2023 Tea is one of the healthiest beverages around; most natural blends are loaded with antioxidants, a moderated amount of energy-boosting caffeine and an amino acid known as L-theanine. Zee Krstic, Good Housekeeping, 21 Nov. 2022 Where coffee used to be a standard choice, natural ingredients such as l-theanine and lion's mane mushroom are now being utilized due to their brain boosting capabilities. Amber Smith, Discover Magazine, 15 Jan. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'theanine.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1950, in the meaning defined above

Time Traveler
The first known use of theanine was in 1950

Dictionary Entries Near theanine

Cite this Entry

“Theanine.” Dictionary, Merriam-Webster, Accessed 18 Jul. 2024.

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