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sou'wester

American  
[sou-wes-ter] / ˌsaʊˈwɛs tər /

noun

  1. a waterproof hat, often of oilskin, having the brim very broad behind and slanted, worn especially by seamen.

  2. an oilskin slicker, fastening with buckles, worn especially by seamen in rough weather.

  3. contraction of southwester.


sou'wester British  
/ saʊˈwɛstə /

noun

  1. a waterproof hat having a very broad rim behind, worn esp by seamen

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of sou'wester

First recorded in 1830–40; reduced form of southwester