Slidell (slīdĕl`), city (1990 pop. 24,124), St. Tammany parish, SE La., near Lake Pontchartrain, there crossed by a bridge to New Orleans; inc. 1888. Originally a shipbuilding and brick-manufacturing town in a farm and timber region, it serves primarily as a bedroom community for the aerospace industry. A large NASA computer complex is there, and a NASA test site is nearby. Seafood and meat products, furniture, chemicals, boats, concrete, apparel, and machinery are produced. Slidell suffered severe damage from Hurricane Katrina in 2005.