triradial (triradial)

[ three, + radius, ray: see radial.] Same as tri radiate. tri radially (tri-rā'di-al-i), adv. With three rays. triradiate (tri-ra'di-at), a. and n. [ The well-known triradiate mark of a leech-bite. Huxley, Anat. Invert., p. 189. 2. In an at., specifically noting one of the lateral fi ures of the brain. -3. In sponges, noting a type of spicule. See II. - Triradiate sulcus. See sulcus. II. n. A triradiate sponge-spicule. The chief modification of the triradiate spicule is due to an elongation of one ray, distinguished as apical, the shorter paired rays being termed basal, and the whole spicule a sagittal triradiate . Encyc. Brit ., XXII. 417. tri radiated (tri-ra'di-a-ted), a. [ triradiate +-ed2.] Same as triradiate . triradiately (tri-ra'di-at-li), adv. In a triradiate manner; in three radiating lines. 6489 tri rectangular (tri-rek-tang'gū-lär), a. [L. tres (tri-), three, + rectus, right, + angulus, angle (see rectangular ).] Having three right angles, as certain spherical triangles. trireme (trī'rēm), n. [F. trirème = Sp. Pg. It. trireme, Diagram and Cro -section of an A then i an Trireme, as restored (1883) by M. M. Raoul Lemaitre. (From "Revue Archéologique.") ber of fighting men, or the best-disciplined, on board, nautical manœuvers being scarcely attempted. The A then i ans, however, in the fifth century B. C., introduced very skilful naval tactics, and made hand-to-hand fighting by the marines subordinate to the attempt to disable the enemy's ship by ramming her amidships, or by crushing her banks of oars. The perfected trireme resembled more closely in theory and tactics the modern steam-ram than any form of ship that has intervened. It was long, narrow, and swift; the modern steam-engine was represented by the mechanical rowing of about 170 men, carefully trained, and under perfect command; and it was entirely independent of its sails, which were not hoisted unle , while cruising, the wind chanced to be favorable. Thucydides writeth that Aminocles the Corinthian built Holland, tr. of Pliny, vii. 56. the first trireme with three rowes of ores to a side.