umbo

noun

um·​bo ˈəm-(ˌ)bō How to pronounce umbo (audio)
plural umbones ˌəm-ˈbō-(ˌ)nēz How to pronounce umbo (audio) or umbos
1
: the boss of a shield
2
: a rounded elevation: such as
a
: an inward projection of the tympanic membrane of the ear
b
: one of the lateral prominences just above the hinge of a bivalve shell
umbonal adjective

Illustration of umbo

Illustration of umbo
  • U umbo 1

Word History

Etymology

borrowed from Latin umbōn-, umbō "boss of a shield, protuberance, projecting piece of land," going back to Indo-European *h3n̥bh-on- or * h3enbh-on-, derivative, with the vowel in a different position ("floating ablaut," German Schwebeablaut), from the base seen in *h3nobh- "hub of a wheel, nave entry 1"

Note: A likely cognate is Old High German amban, ampan "belly of a pig, paunch," a masculine strong noun, though more closely parallel to Latin are traces of an n-stem: a single late Franconian form ambin, presumably dative of a masculine n-stem *ambo; and Old Saxon ambon "paunch" (Latin abdomina), accusative plural of a presumed n-stem *ambo.

First Known Use

1721, in the meaning defined at sense 1

Time Traveler
The first known use of umbo was in 1721

Dictionary Entries Near umbo

Cite this Entry

“Umbo.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/umbo. Accessed 15 Mar. 2024.

Medical Definition

umbo

noun
um·​bo ˈəm-(ˌ)bō How to pronounce umbo (audio)
plural umbones ˌəm-ˈbō-(ˌ)nēz How to pronounce umbo (audio) or umbos
: an elevation in the tympanic membrane of the ear

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