- ancient city in Lydia, W Asia Minor
- city & port in SE Pa., on the Delaware River
Origin of PhiladelphiaClassical Greek philadelphia, brotherly love ; from philos, loving + adelphos, brother: see monadelphous
- An ancient city northeast of the Dead Sea in modern-day Jordan. The chief city of the Ammonites, it was enlarged and embellished by Ptolemy II Philadelphus (285–246 BC) and named in honor of him. Amman, the capital of Jordan, is now on the site.
- An ancient Greek city of Asia Minor in present-day western Turkey. Founded in the second century BC, Philadelphia was a center of early Christianity.
- The largest city of Pennsylvania, in the southeast part of the state on the Delaware River. It was founded as a Quaker colony by William Penn in 1681 on the site of an earlier Swedish settlement. The First and Second Continental Congresses (1774 and 1775–1776) and the Constitutional Convention (1787) met in the city, which served as the capital of the United States from 1790 to 1800.