Technical terms per letter "I"

Idle wheel (driven) is a standard wheel without a keyseat

Induction motor – a motor, the main feature of which is a minor change speed at load change.

Input shaft (drive, high speed) - working name for a part to which reduction gear mechanical energy is supplied.

Involute is the curve drawn by a pencil at the end of a tightly stretched thread winded off a stationary circular cylinder.