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mast 1 (măst)
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n.
1. Nautical
a. A vertical structure consisting of a spar or several spars affixed end-to-end, rising from the keel or deck of a sailing vessel to support the sails.
b. A single spar serving as a part of such a structure: the fore topgallant mast.
2.
a. A vertical pole.
b. A tall vertical antenna, as for a radio.
3. A captain's mast.

[Middle English, from Old English mæst.]
(click for a larger image)
mast1
sailing vessel with three masts

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
 
mast 2 (măst)
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n.
The nuts of forest trees accumulated on the ground, especially considered as a food source for wildlife or for domestic swine.

[Middle English, from Old English mæst.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
 
mast-
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pref.
Variant of masto-.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
 

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.