night-vision

The compound noun "night-vision" is a modern English formation that logically combines two ancient roots to describe a technological capability. The first element, "night," descends from the Proto-Germanic nahts, ultimately from the Proto-Indo-European nókʷts, a fundamental term for the period of darkness. The second element, "vision," traces back to the Latin verb videre ("to see"), from the PIE root weid- meaning "to see" or "to know." The compound's literal meaning, "darkness-seeing," directly reflects its modern application, which began in the mid-20th century to describe electronic devices that amplify low-light or infrared radiation to create a visible image, effectively granting the user sight in conditions of near or total darkness.

Structure: night (dark period) + vision (ability to see) - night: From Old English niht, meaning "the dark period between sunset and sunrise." Its functional role is to specify the condition or time. - vision: From Latin visio (from videre, "to see"), meaning "the act or faculty of seeing." Its functional role is to denote the core concept of sight or visual perception.