The definition of backfill is material used to refill a hole, usually what was previously dug out of the hole.(noun)
Dirt and gravel are examples of backfill.
Backfill is defined as to return soil and other materials to a hole after it was dug.(verb)
An archeologist that puts dirt back into a trench that was dug is an example of to backfill.
See backfill in Webster's New World College Dictionary
transitive verb, intransitive verb
See backfill in American Heritage Dictionary 4
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