Pronunciation: (miz'un-mast", -mäst"; Naut.miz'un-must), [key]
1. the third mast from forward in a vessel having three or more masts. See illus. under quarterdeck.
2. the after and shorter mast of a yawl, ketch, or dandy; jiggermast. Also,miz'en•mast".
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.