lipoic acid

noun

li·​po·​ic acid lī-ˈpō-ik- How to pronounce lipoic acid (audio) li- How to pronounce lipoic acid (audio)
: any of several microbial growth factors
especially : a fatty acid C8H14O2S2 that is essential for the oxidation of alpha-keto acids (such as pyruvic acid) in metabolism

Examples of lipoic acid in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Omega-3 fatty acids plus alpha-lipoic acid. — Megan Nunn, Verywell Health, 29 Apr. 2026 The milk thistle extract and alpha lipoic acid could make the supplement more effective. — Bestreviews, Chicago Tribune, 29 Jan. 2026 Peptides and alpha-lipoic acid are among the ingredients that help lift and tighten the delicate skin on your neck, while niacinamide and vitamin C work to brighten dark spots. — Ava Darrin, ELLE, 16 Nov. 2022 This included an omega-3 fatty acid called alpha lipoic acid (ALA), which offers anti-inflammatory effects. — Lauren O'Connor, Health, 31 Dec. 2025 See All Example Sentences for lipoic acid

Word History

Etymology

lip-, lipo-

First Known Use

circa 1951, in the meaning defined above

Time Traveler
The first known use of lipoic acid was circa 1951

Rhymes for lipoic acid

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Browse Nearby Words

lipography
lipoic acid
lipoid
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Cite this Entry

“Lipoic acid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lipoic%20acid. Accessed 7 Jul. 2026.

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Medical Definition

lipoic acid

noun
li·​po·​ic acid li-ˌpō-ik- How to pronounce lipoic acid (audio) lī- How to pronounce lipoic acid (audio)
: any of several microbial growth factors
especially : a crystalline compound C8H14O2S2 that is essential for the oxidation of alpha-keto acids (as pyruvic acid) in metabolism

called also protogen

More from Merriam-Webster on lipoic acid

Britannica.com: Encyclopedia article about lipoic acid

Last Updated: - Updated example sentences
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