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boot tree

American  

noun

  1. a device of wood, metal, or plastic, inserted in a boot or shoe when it is not being worn, to preserve the shape.


boot tree British  

noun

  1. a shoetree for a boot, often having supports to stretch the leg of the boot

  2. a last for making boots

"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

Etymology

Origin of boot tree

First recorded in 1760–70