The definition of a reservoir is place where a supply of something is collected, especially water.(noun)
An example of a reservoir is an area where large amounts of water are stored.
See reservoir in Webster's New World College Dictionary
Origin: Fr réservoir < réserver: see reserve
See reservoir in American Heritage Dictionary 4
Origin: French réservoir
Origin: , from réserver, to reserve
Origin: , from Old French reserver; see reserve.
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