straight angle

American  

noun

1. the angle formed by two radii of a circle that are drawn to the extremities of an arc equal to one half of the circle; an angle of 180°.

---

straight angle British  

noun

1. an angle of 180°

---

straight angle Scientific  

/ strāt /

1. An angle having a measure of 180°.

---

Etymology

Origin of straight angle

First recorded in 1595–1605

Example Sentences

“There wasn’t a straight angle in the whole building,” Mr. Easter said.

From New York Times • Apr. 12, 2010

Citing everything from the Milky Way to a doughnut, Mr. Fujiwara made straight angle tailoring credible, as well as the rounded version of the wind coats that Mr. Miyake invented three decades ago.

From New York Times • Mar. 5, 2010

Such a term is "straight angle," a concept not used by Euclid, but one that adds so materially to the interest and value of geometry as now to be generally recognized.

From The Teaching of Geometry by Smith, David Eugene

This might be postponed until after the problem to bisect an angle, since it merely requires the bisection of a straight angle; but considering the immaturity of the average pupil, it is better given independently.

From The Teaching of Geometry by Smith, David Eugene

Pupils will find it interesting to cut off the corners of a paper triangle and fit the angles together so as to make a straight angle.

From The Teaching of Geometry by Smith, David Eugene