aux·​in | \ ˈȯk-sən How to pronounce auxin (audio) \

Definition of auxin

1 : any of various usually acidic organic substances that promote cell elongation in plant shoots and usually regulate other growth processes (such as root initiation): such as
b : any of various synthetic substances (such as 2,4-D) resembling indoleacetic acid in activity and used especially in research and agriculture

Other Words from auxin

auxinic \ ȯk-​ˈsi-​nik How to pronounce auxinic (audio) \ adjective

First Known Use of auxin

1933, in the meaning defined at sense 1

History and Etymology for auxin

borrowed from German Auxin, from aux- (borrowed from Greek auxánein "to make grow, increase, strengthen," from aux- "grow" + -an-, verb formative marking completion) + -in -in entry 1 — more at eke entry 2

Note: The name Auxin was introduced by the German chemist Fritz Kögl (1897-1959) and his co-worker at the University of Utrecht, the Dutch chemist Arie Jan Haagen-Smit (1900-77), in the article "Über die Chemie des Wuchsstoffs (Communicated at the meeting of Dec. 19, 1931…by Prof. F.A.F.C. Went)," Koninklijke Akademie van Wetenschappen [Royal NetherlandsAcademy of Sciences], Proceedings of the Section of Sciences, vol. 34 (1931), pp. 1411-1416: "Wir schlagen für den Wuchsstoff die Bezeichnung Auxin (von auxánō [Greek letters] wachsen machen) vor, wobei es sich zur leichteren Namenbildung bei Derivaten empfehlen wird, hierunter die zugrundeliegende frei Säure zu verstehen" ("We suggest for the growth agent the designation auxin (from auxánō to cause to grow), to be recommended for the easier formation of derivative names, including the underlying free acid").

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The first known use of auxin was in 1933

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aux·​in | \ ˈȯk-sən How to pronounce auxin (audio) \

Medical Definition of auxin

: an organic substance that is able in low concentrations to promote elongation of plant shoots and usually to control other specific growth effects broadly : plant hormone

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