The angle that the tangent to a helix makes with the plane normal to the axis of the helix.

The angle at the point of welding between an electrode and a line perpendicular to the weld axis.

1. The angle between the line of sight to a moving target and the line of sight to a point ahead of the target.

2. A dropping angle.

The phase difference between a sinusoidally varying quantity and a reference quantity which varies sinusoidally at the same frequency, when this phase difference is positive. Also known as angle of lead; lead; phase lead.