A '''river''' is a [[long]], moving body of [[water]] having both a [[mouth]] and a source. The longest river in the [[United States]] is the [[Mississippi River]], while the longest in the world is the [[Nile River]]. | A '''river''' is a [[long]], moving body of [[water]] having both a [[mouth]] and a source. The longest river in the [[United States]] is the [[Mississippi River]], while the longest in the world is the [[Nile River]]. |