[ noh-smoh-king ]
/ ˌnoʊˈsmoʊ kɪŋ /
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Word Origin and History for no-smoking
1905; the sign wording itself is attested by 1817.
Smoking is a vice to [sic] -- and a national one, of such magnitude that railroad corporations throughout all their routes in the United States, have a special command in large letters, conspicuously placed at depots and inside of the cars -- "No smoking allowed here." ["The Sailor's Magazine," December 1840]
Online Etymology Dictionary, © 2010 Douglas Harper