Merriam-Webster Collegiate Dictionary - mast

 I. noun  Etymology: Middle English, from Old English m?st; akin to Old High German ~ ~, Latin malus  Date: before 12th century  1. a long pole or spar rising from the keel or deck of a ship and supporting the yards, booms, and rigging  2. a slender vertical or nearly vertical structure (as an upright post in various cranes)  3. a disciplinary proceeding at which the commanding officer of a naval unit hears and disposes of cases against enlisted men — called also captain's ~  • ~ed adjective  II. transitive verb  Date: circa 1513 to furnish with a ~  III. noun  Etymology: Middle English, from Old English m?st; akin to Old High German ~ food, ~, and probably to Old English mete food — more at meat  Date: before 12th century nuts (as acorns) accumulated on the forest floor and often serving as food for animals