trapezii

Plural of trapezius. trapezium (trā-pē'zi-um), n.; pl. trapezia, tra peziums (-a, -umz). [L. trapezium, trapezoid i form or legs), Trapezium. In like manner, a trapezium (πραπέζιον) originally signifies a table, and thus might denote any form; but as the tables of the Greeks had one side shorter than the opposite one, such a figure was at first called a trapezium . Afterwards the term was made to signify any figure with four unequal sides, a name being more needful in geometry for this kind of figure than for the original form. Whewell, Philos. of Inductive Sciences, I., p. 1. 2. In an at.: (a) Acro -band of fibers near the lower border of the pons Varolii, pa ing from the region of the acce ory auditory nucleus to the raphe. They may come, in part, down from the cerebellum or up from the restiform body, as well as from the region mentioned, and seem to terminate in the superior olive of the same side, or in the superior olive, the lemniscus, and acce ory auditory nucleus of the opposite side. A group of large-sized ganglion-cells among the fibers is called the nucleus trapezii. Also called corpus trapezoides. (b) The bone on the radial side of the distal row of carpal bones, articulating with the metacarpal bone of the thumb; carpale I. of the typical carpus, whatever its actual shape. Also called multangulum majus. See cuts under Pe ri odactyla, scapholunar, and hand. - Nucleus trapezii. See def. 2 (a). - Oblique ridge of the trapezium. See oblique. trapezius (trā-pē'zi-us), n.; pl. trapezii (-1). [NL. (sc. musculus ), occipital bone, the lig amentum nuchæ and the spines of the last cervical and of all the thoracic vertebræ, and is inserted into the outer third of the clavicle and the acromion and spine of the scapula. Each trapezius is triangular, and with its fellow of the opposite side forms a somewhat diamond-shaped figure, little like the trapezium of geometry. Also called cucullaris and cowl - muscle or shawl-muscle. See cut under muscle1. IMG:content-0773.png:[graphic] trapezohedral (trā-pē-zō-hedral), a. [ hemihedrism, tetartohedrism. See nouns. bounded by twenty-four equal and similar trapezoidal planes; a tetragonal trisoctahedron. - 2. Any solid having trapezoidal faces, as the trigonal trapezohedron of a quartz crystal. See tetartohedrism. Tetragonal Trisoctahedron, or Trapezohedron. Also trapezihedron . trapezoid (trā-pēʼzoid), a . and n. [F. trapé zoïde = Sp. trapezoide (NL. trapezoides , as a noun also trapezoideum ), εἶδος , form.] I. a . Having the shape of a trapezoid. See II., 1. Segments much compre ed, trapezoid . H. C. Wood , Fresh-Water Algæ, p. 158. Trapezoid bone. See II., 2. - Trapezoid ligament. See ligament . - Trapezoid line. See line2 . II. n. 1. In geom., a plane four-sided figure having two of its opposite sides parallel, and the other two not so.-2. In an at. and zoöl., the trapezoid bone, one of the bones of the wrist, so called from its shape; the second one of the Trapezoid, 1. distal row of carpal bones, on the radial or thumb side, between the trapezium and the magnum, in special relation with the head of the second metacarpal bone; carpale II. of the typical carpus. Also called multangulum minus, and trapezoides, trapezoideum. See cuts under Artiodactyl a, pisiform, hand, and scapho lunar.