Webster's Revised Unabridged Dictionary · 1913

Mast

Mast (mȧst) , noun

[Anglo-Saxon maest, fem.; akin to German mast, and English meat. See Meat.]

The fruit of the oak and beech, or other forest trees; nuts; acorns.
Oak mast, and beech,... they eat. — Chapman
Swine under an oak filling themselves with the mast. — South

Mast , noun

[Anglo-Saxon maest, masc.; akin to Dutch, German, Danish, & Swedish mast, Icelandic mastr, and perh. to Latin malus.]

1.
(Nautical) 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.<--sic--> — Milton

The most common general names of masts are foremast, mainmast, and mizzenmast, each of which may be made of separate spars.

2.
(Machinery) 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.
Collocations (3)
Afore the mast or 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.

Mast , transitive verb

To furnish with a mast or masts; to put the masts of in position; as, to mast a ship.