Auxin
/ˈɔːksɪn/noun
A plant hormone that regulates growth, especially cell elongation, root formation, and directional responses to light and gravity.
Did you know?The name comes from Ancient Greek for “to increase,” and auxin can make a plant bend toward light by moving unevenly through its tissues.
Etymological Timeline
Proto-Indo-European
PIE
*aug-
“To increase, grow, or become greater”
Ancient Greek
Greek
αὐξάνω (auxanō)
“I increase, make grow, or enlarge”
Ancient Greek
Greek
αὔξησις (auxēsis)
“Growth, increase, or augmentation”
19th Century
Scientific English
auxesis
“Growth or increase, formed from the Greek root aux-”
1926
English
auxin
“A growth-promoting substance in plants; coined from Greek auxein, “to increase””
Modern English
English
auxin
“A plant hormone controlling growth responses such as elongation, rooting, and phototropism”