sensor
UK: ˈsɛnsə | US: ˈsɛnsər
n. a device that detects or measures physical properties (e.g., light, heat, motion) and responds with a signal
n. (biology) a sensory organ or cell that reacts to stimuli
Derived from Latin sensus (past participle of sentire, "to feel"), sensor entered English in the mid-19th century via scientific terminology. The morpheme sens preserves the core idea of perception, while -or denotes an instrument or agent (e.g., "detector," "actor"). The word reflects a logical progression from biological senses (e.g., human touch) to mechanical detection (e.g., electronic sensors).
The thermostat uses a temperature sensor to regulate the room.
Insects have specialized sensors to detect chemical signals.
The car’s parking sensor alerts the driver to nearby obstacles.
Scientists developed a nanosensor to monitor air pollution.
Her phone’s light sensor adjusts the screen brightness automatically.