1. A thermometer that uses a transducing element (a device that converts an input signal of one form into an output signal of a different form) whose element properties are a function of its thermal state.
2. A thermometer that uses thermoelectric current to measure temperature.
3. An instrument which utilizes an electrical means to measure temperature; such as, a thermocouple or resistance thermometer.
4. A thermometer indicating temperature variations by means of electrical current flowing through a circuit in which a galvanometer is inserted.

The sensitive element can be an electrical resistance whose value changes with temperature, or a thermocouple (formed by two soldered metals), which also generates specific quantities of current at different temperatures.