WAAC may refer to:
- WAAC (FM), a radio station (92.9 FM) licensed to Valdosta, Georgia, United States
- West African Airways Corporation
- Western Association for Art Conservation a nonprofit regional membership organization for conservation professionals based in the Western United States
- WAAC (Nigeria), an airline that succeeded West African Airways Corporation after its folding
- Women's Army Auxiliary Corps (Britain), a branch of the British military in the First World War
- Women's Army Corps, once abbreviated WAAC, a branch of the U.S. military in the Second World War
- Washington-Alexandria Architecture Center, an extension branch of the College of Design and Architecture of Virginia Tech
- Win At All Costs - Motto of the West London Lacrosse Club