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blister rust

noun Plant Pathology.
  1. a disease, especially of white pines, characterized by cankers and in the spring by blisters on the stems, caused by a rust fungus of the genus Cronartium.

Origin of blister rust

First recorded in 1915–20
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for blister rust

blister rust

noun
  1. a disease of certain pines caused by rust fungi of the genus Cronartium, causing swellings on the bark from which orange masses of spores are released
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