sensor

Definition

A device or organ that detects certain external stimuli and responds in a distinctive manner.

Etymology

Originated 1925–30, formed as a Latin loanword from sentiō (“to feel”) + -tor (“-er”). By surface analysis, sense + -or.

Example Sentences

• "The smoke sensor triggered the alarm."
• "Modern phones contain a light sensor that adjusts brightness."
• "A motion sensor detected movement in the empty room."