• (RP) enPR: mäst, IPA: /mɑːst/
• (America, Canada, Northern England) IPA: /mæst/

From Middle English mast, from Old English mæst, from Proto-West Germanic *mast, from Proto-Germanic *mastaz, from Proto-Indo-European *mazdos.

mast (plural masts)

1. (nautical, communications, aviation) A tall, slim post or tower, usually tapering upward, used to support, for example, sails or observation platforms on a ship, the main rotor of a helicopter, flags, floodlights, meteorological instruments, or communications equipment, such as an aerial, usually supported by guy-wires (except in the case of a helicopter). [from 9th c.]
2. (naval) A non-judicial punishment ("NJP"); a disciplinary hearing under which a commanding officer studies and disposes of cases involving those under his command. [from 17th c.]

• French: mât
• German: Mast
• Italian: albero
• Portuguese: mastro
• Russian: ма́чта
• Spanish: mástil

mast (masts, present participle masting; simple past and past participle masted)

1. To supply and fit a mast to (a ship). [from 16th c.]

• Italian: alberare, inalberare

From Old English mæst and mæstan ("to fatten"), from gmw -; probably related to meat.

mast

1. The fruit of forest-trees (beech, oak, chestnut, pecan, etc.), especially if having fallen from the tree, used as fodder for pigs and other animals. [from 10th c.]
   • c. 1609, George Chapman, Homer, Prince of Poets [translation of Odyssey]:

     She shut them straight in sties, and gave them meat: / Oak-mast, and beech, and cornel fruit, they eat,

   • 1697, Virgil, “The Second Book of the Georgics”, in John Dryden, transl., The Works of Virgil: Containing His Pastorals, Georgics, and Æneis. […], London: […] Jacob Tonson, […], →OCLC ↗, page 93 ↗, lines 755–756:

     The Winter comes, and then the falling Maſt, / For greedy Swine, provides a full repaſt.

   • 1715, Robert South, “A Sermon on Proverbs i. 32.”, in Twelve Sermons Preached at Several Times, and upon Several Occasions, volume IV, London: […] G. James, for Jonah Bowyer […], →OCLC ↗, pages 73–74 ↗:

     [T]hey feed and grovel like Swine under an Oak, filling themſelves with the Maſt, but never ſo much as looking up, either to the Bows that bore, or the Hands that ſhook it down.

• French: faine (of beech tree)
• German: Mast

mast (masts, present participle masting; simple past and past participle masted)

1. (of swine and other animals) To feed on forest seed or fruit.
2. (agriculture, forestry, ecology, of a population of plants) To produce a very large quantity of fruit or seed in certain years but not others.

mast (uncountable)

1. (bodybuilding slang) The anabolic steroid drostanolone propionate, also known as Masteron

From French masse, with -t probably after Etymology 1, above.

mast (plural masts)

1. (obsolete, billiards) A type of heavy cue, with the broad end of which one strikes the ball. [18th–19th c.]
   • 1751, [Tobias] Smollett, The Adventures of Peregrine Pickle […], volume (please specify |volume=I to IV), London: Harrison and Co., […], →OCLC ↗:

     Godfrey thus conquered, pretended to lose his temper, curs'd his own ill luck, swore that the table had a cast, and that the balls did not run true, changed his mast, and with great warmth challenged his enemy to double his sum.

• mast cell

• As a Dutch - surname, from the noun mast.
• Also as a Dutch surname, from the noun mast (sense 2).
• As a German - and Swiss German - surname, from the noun Mast, itself related to the sense of "fodder" above.

1. Surname.

mast (plural masts)

1. (emergency medicine, military) Initialism of military antishock trousers; inflatable trousers that apply pressure to the inferior half of a patient's body to decrease blood loss and prevent the onset of shock, similar to a tourniquet.

• PASG