Apalachin is a census-designated place within the Town of Owego in Tioga County, New York, United States. The population was 1,131 in the 2010 census. The CDP is named after Apalachin Creek. A…Apalachin is a census-designated place within the Town of Owego in Tioga County, New York, United States. The population was 1,131 in the 2010 census. The CDP is named after Apalachin Creek. Apalachin means "from where the messenger returned" in Lenape.