• Mainmast

    Alternative forms

    Origin

    main + mast

    Full definition of mainmast

    Noun

    mainmast

    (plural mainmasts)
    1. (nautical) The chief, and tallest mast of a sailing ship that has more than one mast.

    Usage notes

    On a ship with three or more masts, it is the second mast from the bow.

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