| 释义 |
right angle
[f. right a. 3 + angle n.2]
1. Math.
a. An angle of 90°; = rectangle n. 2.
c1391Chaucer Astrol. ii. §26 This forseid rihte orisonte..diuideth the equinoxial in-to riht Angles. 1551Recorde Pathw. Knowl. i. Defin., A blunt or brode corner is greater then is a square angle, and his lines do parte more in sonder then in a right angle. 1570Billingsley Euclid i. post. iv. 6 All right angles are equall the one to the other. 1611Florio, Retto angolo, a right angle or corner. 1726Swift Gulliver iii. ii, Their Houses are very ill built, the Walls bevil, without one Right-Angle in any Apartment. 1798Hutton Course Math. (1799) I. 331 These planes make with each other two angles whose sum is equal to two right angles. 1880MacCormac Antiseptic Surg. 11 The right leg was at a right angle with the thigh when the limb was extended.
b. at right angles, † in right angle, perpendicularly (to another line, etc.); so as to form an angle of 90°.
1679Moxon Math. Dict. (1701) 23 Cutting the Horizon at Right Angles. 1687A. Lovell tr. Thevenot's Trav. ii. 145 There are six figures on each side..and as many on the border in right Angle. 1734–96[see axis1 7]. 1837Lockhart Scott III. iii. 128 [His] residence was then in George Street, situated very near to, and at right angles with, North Castle Street. 1892Speaker 3 Sept. 289/2 The high road..runs at right-angles to..the lane.
2. attrib. and Comb., as right-angle prism; right-angle fold Printing, a fold at right angles to a previous fold; so right-angle folding.
1931H. Jahn Hand Composition xvi. 264 Models..which operate at high speed on both parallel and *right-angle fold work. 1946A. Monkman in H. Whetton Pract. Printing & Binding v. 59 Machines are available to fold large and small sheets and for parallel or right-angle folding. 1956H. Williamson Methods of Book Design xix. 312 Some machines are equipped with turn-tables, so that..successive parallel folds can be converted at will into right-angle folds. 1972A. G. Martin Finishing Processes in Printing ii. 19 When a number of single sheets are collectively folded once, the technique is known as ‘lump folding’. This method is used for make-up of account-book sections and no right-angle folds are employed.
1884Knight Dict. Mech. Suppl., *Rightangle Prism, an attachment to the microscope stand for throwing light upon an object. |