: a plant hormone C15H20O4 that is a sesquiterpene widespread in nature and that typically promotes leaf abscission and dormancy and has an inhibitory effect on cell elongation : abscisic acid

Word History

Etymology

abscision (variant of abscission) + -in entry 1

First Known Use

1961, in the meaning defined above

Time Traveler
The first known use of abscisin was in 1961

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Cite this Entry

“Abscisin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/abscisin. Accessed 29 Aug. 2026.

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