'Pilot lamp' definitions:

Definition of 'pilot lamp'

From: WordNet
noun
Indicator consisting of a light to indicate whether power is on or a motor is in operation [syn: pilot light, pilot lamp, indicator lamp]

Definition of 'Pilot lamp'

From: GCIDE
  • Pilot lamp \Pilot lamp\ or Pilot light \Pilot light\ (Elec.)
  • 1. A small incandescent telltale lamp on a dynamo or battery circuit to show approximately by its brightness the voltage of the current. [Webster 1913 Suppl.]
  • 2. a small light on an electrical device to indicate whether the device is in operation or that the power is on. [PJC]