olein

noun

ole·in ˈō-lē-ən

1

: an ester of glycerol and oleic acid

2

: the liquid portion of a fat

Word History

Etymology

French oléine, from Latin oleum

First Known Use

1838, in the meaning defined at sense 1

Time Traveler

The first known use of olein was in 1838

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Browse Nearby Words

oleiferous

olein

Olekma

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Cite this Entry

Style

“Olein.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/olein. Accessed 6 Feb. 2026.

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Medical Definition

olein

noun

ole·in ˈō-lē-ən

: an ester of glycerol and oleic acid

called also triolein

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