The definition of an acre is a unit of measure that is equal to 43,560 square feet or a square which measures 208.71 feet by 208.71 feet.(noun)
A standard National Football League field not including the end zones is an example of something that is just over an acre.
See acre in Webster's New World College Dictionary
Origin: ME < OE æcer, field (akin to Goth akrs, Ger acker, L ager) < IE *aĝros (> Gr agros), field, lit., place to which cattle are driven < base *a-: see act
See acre in American Heritage Dictionary 4
Origin: Middle English aker, field, acre
Origin: , from Old English ǽcer; see agro- in Indo-European roots.
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