美利堅合眾國（英語：United States of America，縮寫：USA），簡稱美國、美利堅（英語：America）或合眾國（英語：United States，縮寫：US），是位於北美洲的聯邦制共和國。其由50個州、首都華盛頓哥倫比亞特區和326個印第安人保留地組成[17]；在聯邦外，其主張對5個離岸自治領土及若干外島擁有主權[註 3]。美國領土面積為9,372,610平方公里[10][註 4]，為北美第二（次於加拿大），世界第三或第四[19]。截至2020年初，美國總人口約為3.3億人[20]，是世界第三人口大國[21][22]、也是人口最多的發達國家、以及美洲人口最多的國家。美國有着來自世界各地的大量移民，是世界上民族和文化最多元的國家之一[23]。美國國土的地形與氣候複雜，生物多樣性齊全[24]。 The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic consisting of 50 states and a federal capital district, Washington, D.C. The 48 contiguous states border Canada to the north and Mexico to the south, with the semi-exclave of Alaska in the northwest and the archipelago of Hawaii in the Pacific Ocean. The United States also asserts sovereignty over five major island territories and various uninhabited islands in Oceania and the Caribbean.[i] It is a megadiverse country, with the world's third-largest land area[c] and third-largest population, exceeding 341 million.[j]
