Protractor (redirected from protractor muscles)

protractor

Instrument for constructing and measuring plane angles. The simplest protractor is a semicircular disk marked in degrees from 0° to 180°. A more complex protractor, for plotting position on navigation charts, is called a three-arm protractor, or station pointer, and consists of a circular scale connected to three arms. The centre arm is fixed, while the outer two can be rotated to any desired angle relative to the centre one. A related instrument is the course protractor, which allows navigators to measure the angular distance between north and the course plotted on a navigation chart.

---

protractor

1. an instrument for measuring or drawing angles on paper, usually a flat semicircular transparent plastic sheet graduated in degrees

2. a surgical instrument for removing a bullet from the body

3. Anatomy a former term for extensor

---

protractor [′prō‚trak·tər]

(engineering)

A semicircular instrument used to construct and measure angles formed by intersecting lines of a plane; the midpoint of the diameter of the semicircle is marked and serves as the vertex of angles constructed or measured.

---

protractor

An instrument graduated in angular degrees for measuring or laying out angles.

---

Protractor 

an instrument used to construct and measure angles in sketches and on charts. A protractor consists of a straightedge and a semicircle that is graduated in degrees from 0° to 180°. The precision of a protractor increases as its size becomes larger: the larger the semicircle, the smaller the value of a division. Protractors for very precise construction and measurement of angles—for example, in navigation—are equipped with a transparent straightedge and a goniometric vernier that rotates about the midpoint of the diameter of the semicircle.