Astrophysics

La chandelle standard and « the standard candle » are the same term twice, and the noun inside each is the same Latin word: candela, from candere, to shine. English kept it as the ordinary name of the object. French did not. The everyday French word is la bougie, and that is not a Latin word at all: it is the name of the Algerian port the French called Bougie, today Béjaïa, which shipped the wax the candles were made of — a place turned into a thing, the way « denim » and « cashmere » were in English. That left la chandelle to grow old. It survives in the workshop and above all in fixed phrases: le jeu n’en vaut pas la chandelle, brûler la chandelle par les deux bouts, devoir une fière chandelle à quelqu’un, which is to owe somebody a great deal, and tenir la chandelle, to be the unwanted third person on somebody else’s evening. Astronomy wanted a word with the old workshop in it and reached past bougie for it, which is why the technical term lines up with English exactly where the ordinary vocabulary does not.