L-tryptophan

noun

L-tryp·​to·​phan ˈel-ˈtrip-tə-ˌfan How to pronounce L-tryptophan (audio)
: the levorotatory form of tryptophan that is a precursor of serotonin and was used formerly as a dietary supplement especially to promote sleep and relieve depression

Word History

First Known Use

1949, in the meaning defined above

Time Traveler
The first known use of L-tryptophan was in 1949

Dictionary Entries Near L-tryptophan

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L-tryptophan

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Cite this Entry

“L-tryptophan.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/L-tryptophan. Accessed 23 Mar. 2023.

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Medical Definition

L-tryptophan

noun
L-tryp·​to·​phan ˈel-ˈtrip-tə-ˌfan How to pronounce L-tryptophan (audio)
: the levorotatory form of tryptophan that is a precursor of serotonin and was formerly used in some health food preparations in the belief that it promoted sleep and relieved depression see eosinophilia-myalgia syndrome
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