Soda ash Meaning, Definition & Usage

  1. noun a sodium salt of carbonic acid; used in making soap powders and glass and paper
    sodium carbonate; sal soda; washing soda; soda.

WordNet

Definitions
  1. crude sodium carbonate; so called because formerly obtained from the ashes of sea plants and certain other plants, as saltwort (Salsola). See under Sodium.

Webster 1913