river in SE Iraq, formed by the confluence of the Tigris & Euphrates rivers & flowing southeast into the Persian Gulf: 120 mi (193 km)
See Shatt-al-Arab in American Heritage Dictionary 4
or Shatt-al-Ar·ab(shătˈ ăl ărˈəb, shätˈ äl)
A river channel, about 193 km (120 mi) long, of southeast Iraq formed by the confluence of the Tigris and Euphrates rivers and flowing southeast to the Persian Gulf. The Shatt al Arab forms part of the Iraq-Iran border, and navigation rights to the channel have long been disputed by the two countries.