cosine

In a right triangle, the ratio of the length of the side adjacent to the angle divided by the hypotenuse.

gage block

A hardened steel block that is manufactured with highly accurate dimensions. Gage blocks are available in a set of standardized lengths.

gage pin

A cylindrical pin often used with the sine bar, which helps determine a range of precise measurements. A gage pin provides an easily accessible surface and a known height from which you can measure all distances and edges.

height gage

A type of measuring instrument with a precision finished base, a beam that is at a right angle to the base, and an indicator.

hypotenuse

The longest side of a right triangle. The hypotenuse is always opposite the 90° angle in a right triangle.

reference angle

The measured, or known angle in a right triangle other than the 90° angle.

right triangle

A triangle containing one angle that measures exactly 90 degrees.

sine

In a right triangle, the ratio of the length of the side opposite the angle divided by the hypotenuse.

sine bar

A steel bar with a matching cylinder on each end that is used for setting up work at various angles for the machining or inspection of parts. A sine bar is ground and lapped to a high accuracy.

surface plate

A hard, flat surface, usually made of granite, which is used as a base for inspecting parts.

tangent

In a right triangle, the ratio of the length of the side opposite the angle divided by the adjacent side.

transversal line

A line that intersects two or more lines at different points.

trigonometric ratio

A ratio that describes a relationship between a side and angle of a right triangle.

vertical angles

Two angles that share the same vertex and are positioned directly opposite one another. Vertical angles are formed whenever two lines intersect.
