The angle with the horizontal at onset of movement is called the tilt-angle.

The angle formed at this junction is called gonial angle.

For a line, these angles are called the trend and the plunge.

This angle varies sinusoidally through the year and is called B0.

Two angles that sum to one right angle (90 ) are called complementary angles.

Thus, an angle measuring 90 degrees is called a right angle.

The angle is called dip and varies with place, so compasses can be corrected for different zones.

Two angles are called complementary if their sum is a right angle.

Any angle above a horizontal line was called random-shot.

The angle at which this occurs is called the critical angle of attack.