Laboratory medicine

The eighth entry is a fórmula leucocitária, and it is the one line on this sheet an English reader should not carry over word for word. « Formula » in English is a rule written in symbols, a set of words repeated unchanged, or, in a British chemist’s, the milk a baby is fed on. None of those is what the Portuguese phrase names. It names the breakdown of the white cells into their kinds, and a British laboratory prints that as « differential white cell count », which a doctor shortens on the ward to « the differential ». The trap is narrow and therefore easy to walk into, because a fórmula and « formula » agree almost everywhere else: a fórmula química, uma fórmula matemática, uma fórmula de cortesia. It is only in the laboratory that the two part company. The same habit governs the entries beside it, where o hemograma is a « full blood count » and o ionograma is « urea and electrolytes ». Portuguese names these panels with Greek and Latin; a British report names them by what is counted, and that plainer name is the one to reach for.