CIW

CIW has multiple meanings:


 * California Institution for Women, a state prison in the USA
 * Canadian Index of Wellbeing, that measures the wellbeing of Canadians over time
 * Carnegie Institution of Washington
 * Chicago and Illinois Western Railroad
 * Central Indiana and Western Railroad
 * Certified Internet Web Professional
 * Coalition of Immokalee Workers
 * Computational Intensive Workload
 * ISO 639 language designation for Southwestern dialect of the Anishinaabe language, often called the "Chippewa language."
 * Close-in weapon system