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scrap heap

or scrap·heap

noun

a pile of old, discarded material, as metal.
a place for dumping old, useless things.

Origin of scrap heap

First recorded in 1830–40; scrap1 + heap
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for scrapheap

scrapheap

noun

a pile of discarded material
on the scrapheap (of people or things) having outlived their usefulness
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