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n. pl. um·bo·nes (ŭm-bō′nēz) or um·bos
1. The boss or knob at the center of a shield.
a. Biology A knoblike protuberance arising from a surface, as the prominence near the hinge of a bivalve shell or the raised area in the center of the cap of a mushroom.
b. Anatomy A small projection at the center of the outer surface of the eardrum.
um′bo·nal (ŭm′bə-nəl, ŭm-bō′nəl) adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
n, pl umbones (ʌmˈbəʊniːz) or umbos
1. (Botany) a small hump projecting from the centre of the cap in certain mushrooms
2. (Zoology) a hooked prominence occurring at the apex of each half of the shell of a bivalve mollusc
3. (Anatomy) anatomy the slightly convex area at the centre of the outer surface of the eardrum, where the malleus is attached on the internal surface
4. (Arms & Armour (excluding Firearms)) a large projecting central boss on a shield, esp on a Saxon shield
[C18: from Latin: boss of a shield, projecting piece]
umbonate, umbonal, umbonic adj
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
n., pl. um•bo•nes (ʌmˈboʊ niz) um•bos.
1. a boss on a shield.
2. any similar boss or protuberance.
3. the beak of a bivalve shell; the protuberance of each valve above the hinge.
4. the raised area on the inner surface of the tympanic membrane, where the malleus is attached.
[1715–25; < Latin umbō; akin to umbilīcus (see umbilicus)]
um′bo•nal (-bə nl) adj.
um′bo•nate (-nɪt, -ˌneɪt) adj.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
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|Noun||1.||umbo - a slight rounded elevation where the malleus attaches to the eardrum|
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