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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.



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’.

References in periodicals archive ?
Ecio con soros anfigenos, dispersos; eciosporas elipsoides a obovoides, (21)24-30(-35) x (17-)19-25(-29) [micron]m; pared equinulada, delgada, 1,5-2 [micron]m de grosor, de color marron-castano; poros germinativos 2-3 casi supraecuatoriales, con ligeros umbos o sin ellos.
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.
El analisis de las huellas de manufactura permitio identificar al pedernal como la herramienta que se empleo para desgastar los umbos y las superficies externas de las conchas, asi como para la aplicacion de los pulidos.
Umbo, C 2014, 'Australia maintain position on asylum seekers', Papua New Guinea Today, 18 February, 2014, viewed 5 November, 2014,
Morfologicamente nos encontramos ante un "vaso" que se puede coger con una sola mano, a la que se adapta perfectamente para realizar la libacion, ya que mientras el pulgar agarra el borde, el dedo indice se apoya el interior del umbo por el exterior.
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.
In addition, some restorations in the sinus, umbo and left hand are detectable when comparing the images presented by the Commission of Monuments (Elorza, 1974: tav.
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.