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

Example Sentences

Recent Examples on the Web 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 The formula includes: caffeine, L-theanine, Rhodiola rosea, and ashwagandha. Amber Smith, Discover Magazine, 17 Oct. 2022 Instant Knockout increases energy levels with natural ingredients like green tea extract, cayenne pepper seeds, vitamin B12, black pepper extract, caffeine, and L-theanine. Dallas News, 20 Sep. 2022 These products typically contain ingredients like L-theanine, chamomile, lavender oil, and other natural ingredients that can have a calming effect on dogs. Amber Smith, Discover Magazine, 9 Nov. 2022 Our caffeine-free mixture of chromium, seaweed extract + L-theanine does the trick. Amber Smith, Discover Magazine, 3 Dec. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'theanine.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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 27 Mar. 2023.

Last Updated: - Updated example sentences
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