umbo

[ uhm-boh ]

noun,plural um·bo·nes [uhm-boh-neez], /ʌmˈboʊ niz/, um·bos.
  1. a boss on a shield, as one at the center of a circular shield.

  2. any similar boss or protuberance.

  1. Zoology. the beak of a bivalve shell; the protuberance of each valve above the hinge.

  2. Anatomy. the depressed area on the outer surface of the tympanic membrane.

  3. a blunt or rounded protuberance arising from a surface, as on a pine cone scale.

Origin of umbo

1
1715–25; <Latin umbō boss (of a shield), knob, projecting part; akin to umbilīcus (see umbilicus)

Words Nearby umbo

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How to use umbo in a sentence

British Dictionary definitions for umbo

umbo

/ (ˈʌmbəʊ) /


nounplural umbones (ʌmˈbəʊniːz) or umbos
  1. a small hump projecting from the centre of the cap in certain mushrooms

  2. a hooked prominence occurring at the apex of each half of the shell of a bivalve mollusc

  1. anatomy the slightly convex area at the centre of the outer surface of the eardrum, where the malleus is attached on the internal surface

  2. a large projecting central boss on a shield, esp on a Saxon shield

Origin of umbo

1
C18: from Latin: boss of a shield, projecting piece

Derived forms of umbo

  • umbonate (ˈʌmbənɪt, -ˌneɪt), umbonal (ˈʌmbənəl) or umbonic (ʌmˈbɒnɪk), adjective

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