Fluorescences

Part of speech: noun

Definitions

1. The emission of light by a substance that has absorbed light or other electromagnetic radiation
2. A process in which certain materials emit visible light when illuminated by ultraviolet light or other radiation
3. The phenomenon by which some materials glow brightly while absorbing and re-emitting light, typically occurring immediately after exposure to energy sources

Etymology: George Gabriel Stokes, the Cambridge physicist, coined "fluorescence" in 1852 when he was studying a glowing substance, and he named the phenomenon after the mineral that showed it most clearly. That mineral was fluorspar, the name for what mineralogists today call fluorite. Stokes built the new word by attaching the suffix "-escence" to "fluor", the stem of fluorspar, so the name points to the mineral rather than to any general idea of light. The "fluor" part traces back to Latin "fluere", meaning "to flow", which is also the source of "fluid" and "flux". Fluorspar got its name because miners and metalworkers used it as a flux, a substance that made ores melt more easily. The "-ite" ending on fluorite is a later mineralogical suffix, so the older name fluorspar has the more transparent history. "Fluorescences" is simply the plural of "fluorescence", and it is used when people mean distinct instances or kinds of this light emission. The noun is therefore the mineral's flowing name carried into physics.

Synonyms: glow, luminescence, radiance, brightness, shine

Antonyms: dullness, darkness, opacity