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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 ?
Pedicle valve had sulcus from umbo to the end of the shell.
5); and 3) a tubuculate ornamentation in the postcentral umbo area (Fig.
lamellus by having comarginal, imbricate lamellae from the umbo to the anterior margin.
Noem voorbeelde van Paulus se gedrag tydens sy ontmoeting met die uMbo wat toon dat hy mooi opgelet het wat goeie Voortrekkermaniere is.
The costae and costellae form high, narrow ridges of about the same width for the most part of the valve surface, with 4-5 ribs per 5 mm at 5 mm from the umbo and along the anterior margin (Pl.
5-4 cm broad; color dark brown when moist, fading to light brown or yellowish-brown, umbo often remaining darker; surface sticky to viscid, smooth and hairless; margin faintly striate.
Each mat has 36 disarticulated oyster shells, which each has a hole drilled in near the umbo, and are then firmly attached using zip ties so that the shells are perpendicular to the mesh.
Elongated and slender Ribeiria with straight dorsal margin, with terminal umbo and with narrow pegma.
SSCDs can cause (1) a significant reduction in sound-induced round-window velocity at low frequencies, (2) small but significant increases in sound-induced stapes and umbo velocities, and (3) a measurable fluid velocity inside the dehiscence.
1) Shell height (SH, the distance in mm between the umbo and shell margin) is the body size measurement for sea scallops.
New Women, New Men' gives us Frantisek Drtikol, Lotte Jacobi, Eva Besnyo and Hans Bellmer; 'Modern Living', Umbo, Ringl+Pit (Witkowsky is enlightening on women photographers) and Paul Wolff, whose view of Hitler's autobahn reminds us of the Nazi embrace of modernity.
Otoliths of Atractoscion differ mainly in the moderate to strongly developed postcentral umbo on the outer face, which is true for otoliths of Bahaba.