Mast, n.
 1. Naut. A pole, or long, strong, round piece of timber, or spar, set upright in a boat or vessel, to sustain the sails, yards, rigging, etc.  A mast may also consist of several pieces of timber united by iron bands, or of a hollow pillar of iron or steel.
 The tallest pine
 Hewn on Norwegian hills, to be the mast
 Of some great ammiral.   --Milton.
 Note: ☞ The most common general names of masts are foremast, mainmast, and mizzenmast, each of which may be made of separate spars.
 2. Mach. The vertical post of a derrick or crane.
 3. Aeronautics A spar or strut to which tie wires or guys are attached for stiffening purposes.
 Afore the mast, Before the mast. See under Afore, and Before.
 Mast coat. See under Coat.
 Mast hoop, one of a number of hoops attached to the fore edge of a boom sail, which slip on the mast as the sail is raised or lowered; also, one of the iron hoops used in making a made mast. See Made.