Pyrometer

Part of speech: noun

Definitions

1. An instrument designed to measure elevated temperatures without direct contact by analyzing thermal radiation emitted from objects
2. A tool that gauges very high heat levels by detecting radiation from a surface without touching it
3. An instrument used to determine elevated temperatures by sensing heat emitted from an object at a distance

Etymology: The name is a straightforward compound: "pyro-" comes from Greek "pûr", meaning fire, and "-meter" comes from Greek "métron", meaning measure. So a pyrometer is, quite literally, a fire-measurer. The Greek "pûr" passed into Latin as "pyr" and from there into English as the combining form "pyro-", which appears in many modern scientific terms. The second element has a more roundabout route. Greek "métron" gave rise to the suffix "-tron" in Greek, and the "-meter" form reached English through French "-mètre", which took it from the same Greek root. English thus borrowed the ending as a ready-made building block, which is why it appears in so many instrument names such as thermometer and barometer. Pyrometer simply joins "pyro-" to that familiar ending, producing a device whose name describes its job: measuring fire-level heat, which in practice means high temperatures from a distance.