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
noun
See backfill in American Heritage Dictionary 4
noun
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