What does abscisin mean?
Abscisin is a plant hormone, identified with what is now called abscisic acid, that plays a central role in how plants shed parts of themselves and cope with adversity. It promotes abscission — the controlled detachment of leaves, fruits, and flowers — and also influences dormancy in buds and seeds, helping plants time their growth to favorable conditions. The term arose in mid-twentieth-century plant physiology, when researchers studying leaf fall and bud dormancy independently isolated the same substance and gave it different names before the chemistry was unified. Today 'abscisin' survives mainly in older literature, having been superseded by 'abscisic acid', but it remains a useful word for understanding how botanists came to map the chemical signals that govern a plant's life cycle. Its root, like that of 'abscission', points to the Latin verb abscindere, meaning to cut off.
nounA plant hormone, now more commonly known as abscisic acid, that promotes the abscission of leaves, fruits, and other plant organs and helps regulate dormancy and responses to stress such as drought.
- A plant hormone (abscisic acid) that promotes the shedding of leaves, fruits, and flowers and regulates dormancy and stress responses.
"The researchers found that abscisin levels rose sharply as the tree prepared to shed its leaves."
"Applying abscisin to the cut stems accelerated the natural drop of the leaves."
"Early studies of bud dormancy were conducted before abscisin was recognized as identical to abscisic acid."
Rarely pluralized; when referring to the hormone as a chemical substance it is typically treated as an uncountable mass noun.
"Different tissues were analyzed for their concentrations of abscisins and related growth regulators."
Before chemists settled on the name abscisic acid, this leaf-dropping hormone was known as 'dormin' — and two rival labs actually discovered it at the same time under different names.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of abscisin
The word abscisin was coined in the mid-twentieth century by plant physiologists who isolated a substance responsible for promoting leaf and fruit fall. It derives from the Latin abscindere ('to cut off'), formed from ab- ('away') and scindere ('to cut or split'), combined with the chemical suffix '-in' used for organic substances. The same Latin root gives English 'abscission' and 'abscissa'. After further research showed the compound was identical to a dormancy-inducing factor called 'dormin', the name abscisic acid became standard, and abscisin fell out of common use.
How abscisin is actually used
Abscisin is chiefly a technical term used in older botanical and plant-physiology literature; contemporary scientific writing almost always uses 'abscisic acid' instead.
Easily confused with abscisin
Abscission is the process by which a plant sheds leaves, fruit, or other parts, whereas abscisin is the hormone associated with promoting that process.
Abcisic acid is the modern chemical name for the same substance once called abscisin; the older term 'abscisin' is now largely historical.