Adel is a city in Cook County, Georgia, United States. As of the 2010 census, the city had a population of 5,344. The city is the county seat of Cook County. The original name of the city was Puddleville. The city's first postmaster, Joel "Uncle Jack" Parrish, wanted to change the name of the city. It is believed that he saw the name "Philadelphia" on a crocus sack, struck out the first and last four letters to create the present name of Adel.