a variety of a 'gas discharge' device
gas discharge light that generates a blue or amber light by exciting a neon gas plasma with two heated electrodes; when the voltage is high enough between the electrodes, the neon gas will break down and begin to conduct electricity, giving off a glow in the process.
Culturally famous high voltage, low pressure bulbs used in outdoor signage.
A neon lamp is a gas discharge lamp containing primarily neon gas at low pressure. The term is also used for similar devices filled with other noble gases, usually to produce different colors.