backfill

[bak-fil]

noun

material used for refilling an excavation.

verb (used with object)

to refill (an excavation).

Origin of backfill

First recorded in 1950–55; back² + fill

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for backfill

backfill

verb

(tr) to refill an excavated trench, esp (in archaeology) at the end of an investigation

noun

the soil used to do this

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

Word Origin and History for backfill

1901 (as backfilling), from back (adj.) + fill (n.). The verb was in use by 1930.