Sentence:  It was April 22, 1831, and a young man was walking down Whitehall in the direction of Parliament Street. He wore shepherd's <WSD>plaid</WSD> trousers and the swallow-tail coat of the day, with a figured muslin cravat wound about his wide-spread collar. 
Meaning of the word marked with <WSD> tags:  A type of twilled woollen cloth, often with a tartan or chequered pattern. (from 16thc.)