Runoff is defined as excess water draining away from land or buildings.(noun)
The overflow of water that drains off of your driveway is an example of runoff.
The definition of a runoff is an additional election held when a first election produces a tie or otherwise does not result in a winner.(noun)
When a first election ties and then a second election is held between the two parties who tied in the original race, this is an example of a runoff.
See runoff in Webster's New World College Dictionary
See runoff in American Heritage Dictionary 4
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