Pronunciation: (sou"wes'tur),[key] —n. 1. a waterproof hat, often of oilskin, having the brim very broad behind and slanted, worn esp. by seamen.
2. an oilskin slicker, fastening with buckles, worn esp. by seamen in rough weather.
3. southwester (def. 1). Also called nor'wester(for defs. 1, 2).