Individual #Tigris_River__Tigris  an Asian river; a tributary of the Euphrates River
  instance of:  river
  part of:  Iraq__Republic_of_Iraq__Al-Iraq__Irak  a republic in the Middle East in western Asia; the ancient civilization of Mesopotamia was in the area now known as Iraq
     part of:  Middle_East__Near_East  the area around the eastern Mediterranean; from Turkey to North Africa and eastward to Iran; the site of such ancient civilizations as Phoenicia and Babylon and Egypt and the birthplace of Judaism and Christianity and Islam; "the Middle East is the cradle of Western civilization"
     part of:  Asia  the largest continent with 60% of the earth's population; it is joined to Europe on the west to form Eurasia; it is the site of some of the world's earliest civilizations
        part of:  Eurasia  the land mass formed by the continents of Europe and Asia
           part of:  eastern_hemisphere__easternhemisphere__orient  the hemisphere that includes Eurasia and Africa and Australia
           part of:  northern_hemisphere  the hemisphere north of the equator
  part of:  Syria__Syrian_Arab_Republic  an Asian republic in the Middle East at the east end of the Mediterranean; site of some of the world's most ancient centers of civilization
     part of:  Middle_East__Near_East  the area around the eastern Mediterranean; from Turkey to North Africa and eastward to Iran; the site of such ancient civilizations as Phoenicia and Babylon and Egypt and the birthplace of Judaism and Christianity and Islam; "the Middle East is the cradle of Western civilization"
     part of:  Asia  the largest continent with 60% of the earth's population; it is joined to Europe on the west to form Eurasia; it is the site of some of the world's earliest civilizations
  part of:  Turkey__Republic_of_Turkey  a Eurasian republic in Asia Minor and the Balkans; achieved independence from the Ottoman Empire in 1923
     part of:  Asia_Minor__Anatolia  a peninsula in southwestern Asia that forms the Asian part of Turkey
        part of:  Asia  the largest continent with 60% of the earth's population; it is joined to Europe on the west to form Eurasia; it is the site of some of the world's earliest civilizations
     part of:  Balkan_Peninsula__Balkans  a large peninsula in southeastern Europe containing the Balkan Mountain Range
        part of:  Europe  the 2nd smallest continent (actually a vast peninsula of Eurasia); the British use `Europe' to refer to all of the continent except the British Isles
           part of:  Eurasia  the land mass formed by the continents of Europe and Asia
     part of:  Middle_East__Near_East  the area around the eastern Mediterranean; from Turkey to North Africa and eastward to Iran; the site of such ancient civilizations as Phoenicia and Babylon and Egypt and the birthplace of Judaism and Christianity and Islam; "the Middle East is the cradle of Western civilization"
     part of:  Mediterranean_region

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