Explosion protection

The sixth entry is l’énergie minimale d’inflammation, and the noun at the end of it is the one an English reader will misread without noticing. French l’inflammation is the catching fire itself, the instant at which a mixture takes light. It belongs to enflammer, to set alight, and to s’enflammer, to catch fire, and half of this list turns on it — la source d’inflammation is the ignition source, la température d’auto-inflammation the temperature at which no source is needed at all. English went the other way entirely and left the word in medicine. « Inflammation » is a red, hot, swollen joint or gum, the body reacting to injury, and nobody hearing it thinks of a flame. The Latin inflammatio carried both readings, and the two languages kept one half each. Two things follow for anybody working between them. Rendering la source d’inflammation as a source of inflammation turns a light switch into a symptom. And in the other direction the trap stays hidden, because in a medical sentence « inflammation » really is l’inflammation — the same form is a false friend on one page and an exact one on the next.