"detector" in the noun sense
1. detector, sensor, sensing element
any device that receives a signal or stimulus (as heat or pressure or light or motion etc.) and responds to it in a distinctive manner
2. detector, demodulator
rectifier that extracts modulation from a radio carrier wave
electronic equipment that detects the presence of radio signals or radioactivity
Source: WordNet® (An amazing lexical database of English)
Princeton University "About WordNet®."
WordNet®. Princeton University. 2010.
View WordNet® License