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corn smut

noun
  1. a disease of corn caused by a fungus, Ustilago maydis, and characterized by blackish, powdery masses of spores on the affected parts of the plant.

Origin of corn smut

First recorded in 1880–85
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for corn smut

corn smut

noun
  1. an ascomycetous parasitic fungus, Ustilago zeae, that causes gall-like deformations on maize grain
  2. the condition produced by this fungus
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