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florigen

[flawr-i-juh n, flohr-]
noun
  1. a hypothetical plant hormone produced in the leaves and transported to the apex to initiate flowering.
Related formsflo·ri·gen·ic, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for florigen

florigen

noun
  1. the hypothetical plant hormone that induces flowering, thought to be synthesized in the leaves as a photoperiodic response and transmitted to the flower buds

Word Origin for florigen

C20: from Latin flōr-, flōs flower + -gen
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012