a tree, Nyssa sylvatica, of eastern North America, having elliptic leaves, dark-blue, berrylike fruit, and wood with a variety of commercial uses.
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Origin of sour gum
An Americanism dating back to 1775–85
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Examples from the Web for black gum
The leaves of the sour-gum, the first tree to turn, showed blood-red.Wild Folk|Samuel Scoville
British Dictionary definitions for black gum
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