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mainmast

American  
[meyn-mast, -mahst, meyn-muhst] / ˈmeɪnˌmæst, -ˌmɑst, ˈmeɪn məst /

noun

Nautical.

  1. the second mast from forward in any ship having two or more masts, mast, except for a yawl, ketch, or dandy.

  2. the larger forward mast of a yawl, ketch, or dandy.

  3. the sole mast of any of various ships, as sloops or cutters.

mainmast British  
/ ˈmeɪnˌmɑːst /

noun

  1. nautical the chief mast of a sailing vessel with two or more masts, being the foremast of a yawl, ketch, or dandy and the second mast from the bow of most others

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of mainmast

First recorded in 1475–85; main 1 + mast 1

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.