umbo

American  

[uhm-boh] / ˈʌm boʊ /

noun

umbones, plural umbos plural

1. a boss on a shield, as one at the center of a circular shield.

2. any similar boss or protuberance.

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

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

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

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umbo British  

/ ˈʌmbənɪt, ʌmˈbɒnɪk, -ˌneɪt, ˈʌmbəʊ, ˈʌmbənəl /

noun

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

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

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Other Word Forms

Derived Forms

• umbonate
  adjective

Inflected Forms

noun

• umbos
  plural
• umbones
  plural

Etymology

Origin of umbo

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

Example Sentences

P. 1.5-2.5 cm. livid brown, finely striate all over, no trace of umbo or fleshy disc; g. adnate, not connected by veins; s. 6-9 cm. slightly striate, polished, pale, base fibrillose; sp.

From European Fungus Flora: Agaricaceae by Massee, George

P. striate, grey, umbo darker; g. greyish white; s. white, pruinose, base brownish, strigosely rooting; sp. globose, aculeate. vitilis, Fr.

From European Fungus Flora: Agaricaceae by Massee, George

P. convex, even, umbo fleshy, bay, shining; g. adnate, ovate, distant; s. solid, firm, wavy, naked, colour of p.; sp.

From European Fungus Flora: Agaricaceae by Massee, George

P. 3-4 cm. white, umbo brownish, striate to middle; g. decurrent; s. equal, hollow upwards, 4-5 cm., even up to torn ring, punctate above, white; sp.

From European Fungus Flora: Agaricaceae by Massee, George

P. 2-5 cm. conic camp. exp. striate up to umbo, dry, brownish, livid, &c.; adnate with decurrent tooth, connected by veins, pinkish when old; s. 5-8 cm. polished, even, glabrous; sp. 6-7 � 4.

From European Fungus Flora: Agaricaceae by Massee, George