Biasing

predetermined voltages or currents establishing proper operating conditions in electronic components

Biasing in electronics is using specific voltages and/or currents at points of an electronic circuit to set an appropriate operating point. The operating point of a device, also known as bias point, is the point that shows (in case of transistor) the direct current, collector-emitter voltage, and the collector current with no input signal.

Three different bias points of vacuum tube
Three different bias points of vacuum tube

The term biasing is usually used with transistors, vacuum tubes or diodes.