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A rounded elevation of the surface of the tympanic membrane.
(invertebrate zoology)
A prominence above the hinge of a bivalve mollusk shell.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



the iron central boss of a shield, which protected the warrior’s hand. Under the hemispherical or conical umbo was a crosspiece by which the shield was held. Shields with umbones were widely used in ancient Greece and Rome and in medieval Europe and Rus’.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
In each animal, the vibrations of the TM (or umbo; Vu), stapes head (Vs), round window (Vw), and the place of the dehiscence (Vd) were measured (Figure 1(d)) before and after the dehiscence was created and when the dehiscence had been repaired using dental cement.
Umbo, C 2014, 'Australia maintain position on asylum seekers', Papua New Guinea Today, 18 February, 2014, viewed 5 November, 2014,
The straight hinge larvae were transformed into the umbo stage on day-5 until day-13.
a) ovocito con cuerpos polares, 1CP: primer cuerpo polar, 2CP: segundo cuerpo polar, O: ovocito, b) estadio transitorio de tres celulas, B: blastomero, LP: lobulo polar, c) estadio de cuatro celulas, d) gastrula temprana, IN: invaginacion celular, e) trocofora, F: flagelo, f) estadio veliger, EC: elevacion central de las valvas bajo de la charnela, g) larva umbada, U: umbo, h) postlarva, D: disoconcha, HL: hueco de la insercion del ligamento de la charnela, i) postlarva, CB: canal de la muesca del biso, AU: auriculas de la concha, j) juvenil, C: costillas, VD: valva derecha, VI: valva izquierda.
Modern art's new muse was the shop window dummy, celebrated in photographs by Umbo (Fig.
Mussel shells were first sectioned through the umbo and epoxied to a microscope slide or plexiglass plate, depending on size.
In most cases, only the exoskeletons of bivalves and gastropods are depicted, with emphasis on the periostracum (the outermost layer of the shell), growth lines, and umbo. This is particularly evident in Plate 18, which contains etched examples of bivalves from the genera Tellina and Fectunculus (Fig.
In a growth-based approach of shell shape, the sagittal outline of shells maybe appropriately parameterised synthetically using three indices associated with three "typical growth vectors" V, V', and V" (Figure 1), each of them extending from the valve umbo A.