American Samoa Abbr. AS An unincorporated territory of the United States in the southern Pacific Ocean northeast of Fiji comprising the eastern islands of the Samoan archipelago. American Samoa has been administered by the United States since 1899. Pago Pago, on Tutuila, the largest island of the group, is the capital.American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.American Samoa n (Placename) the part of Samoa administered by the US. Capital: Pago Pago. Pop: 54 719 (2013 est). Area: 197 sq km (76 sq miles) Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014Amer?ican Samo?a n. the part of Samoa belonging to the U.S., comprising mainly Tutuila and the Manua Islands. 61,819; 76 sq. mi. (197 sq. km). Cap.: Pago Pago. Abbr.: AS Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.