sengan

Old English sengan meant to burn slightly, to expose briefly to flame. The word comes from Proto-Germanic sangjan, a causative verb meaning to cause to sing—possibly from the hissing, singing sound that hair or feathers make when they touch flame. If the etymology holds, to singe originally meant to make fire sing against a surface.

Singeing was a practical craft. Butchers singed pig carcasses to remove bristles. Tailors singed fabric to remove loose fibers and create a smooth finish. Hairdressers singed hair ends with a candle flame—a practice that persisted into the nineteenth century, based on the belief that sealing the hair shaft prevented splitting. The word belonged to workshops and kitchens, not battlefields.

The metaphorical singe arrived in the sixteenth century. To singe someone's beard meant to humiliate them by getting dangerously close. In 1587, Sir Francis Drake attacked the Spanish fleet at Cádiz and reportedly boasted of having singed the King of Spain's beard—a phrase that entered English idiom and stayed.

Modern English keeps singe precisely where it has always been: on the boundary between harmless and harmful. You singe your eyebrows leaning over a candle. You singe a moth that flies too close. The word always implies a near miss, damage that could have been worse. Singe is fire's warning shot.