indoleacetic acid

noun

in·​dole·​ace·​tic acid ˌin-(ˌ)dō-lə-ˈsē-tik- How to pronounce indoleacetic acid (audio)
: a crystalline plant hormone C10H9NO2 that is a naturally occurring auxin promoting growth and rooting of plants

Word History

First Known Use

1937, in the meaning defined above

Time Traveler
The first known use of indoleacetic acid was in 1937

Dictionary Entries Near indoleacetic acid

indole

indoleacetic acid

indolebutyric acid

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Cite this Entry

“Indoleacetic acid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/indoleacetic%20acid. Accessed 1 Dec. 2024.

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Kids Definition

indoleacetic acid

noun
in·​dole·​ace·​tic acid ˈin-ˌdōl-ə-ˌsēt-ik- How to pronounce indoleacetic acid (audio)
: a plant hormone that promotes growth and rooting of plants

Medical Definition

indoleacetic acid

noun
in·​dole·​ace·​tic acid ˈin-ˌdōl-ə-ˌsēt-ik- How to pronounce indoleacetic acid (audio)
: a crystalline compound C10H9NO2 that is formed from tryptophan in plants and animals, is present in small amounts in normal urine, and acts as a growth hormone in plants

called also heteroauxin

More from Merriam-Webster on indoleacetic acid

Britannica.com: Encyclopedia article about indoleacetic acid

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