Lubricants and tribology

Entry twelve is a escoriação, and an English reader who meets it in a gearbox report has met it before in a hospital one. Behind both stands the Latin excoriare, built from ex-, off, and corium, hide: to take the skin off something. English borrowed the word whole and kept it on flesh. « Excoriation » is a graze, a patch of skin rubbed away, and to « excoriate » a colleague is to flay them in words. Nothing in that family was ever let near steel. Portuguese kept the medical sense too, and then let the picture travel: a escoriação is also what a tooth flank looks like once the oil film has thinned, the fine scoring that comes before the two surfaces weld. The term therefore says what the damage actually is, which is that the surface has been skinned. The English word on the datasheet is « scuffing », a plain Germanic noun that carries no hide in it at all, so the image Portuguese hands a reader for nothing has to be learnt here separately, as a label.