Definition of auxin
1 : any of various usually acidic organic substances that promote cell elongation in plant shoots and usually regulate other growth processes (as root initiation): as a : indoleacetic acid b : any of various synthetic substances (as 2,4-D) resembling indoleacetic acid in activity and used especially in research and agriculture
2 : plant hormone
Origin of auxin
International Scientific Vocabulary, from Greek auxein to increase — more at eke
First Known Use: 1933
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