From cunning to credulous

Discreto looks like a word an English reader already owns, and in a sense it is two of them. The Latin past participle discretus meant separated, set apart; it belongs to discernere, to tell one thing from another. English took the word in twice and then used the spelling to divide the labour between the two arrivals. « Discrete » kept the plain sense of separate, countable, standing apart, which is why a statistician speaks of discrete values. « Discreet » took the social sense: somebody who keeps things apart by keeping them quiet. The two are pronounced identically, so the pair is among the commonest spelling slips in English prose, and « discretely » and « discreetly » say quite different things about a person. Portuguese never made that split. Discreto does both jobs in one form: É discreto e nunca fala do que fez is the second sense, while uma variável discreta in a statistics book is the first. The question an English writer has to settle before the word can be put on paper — which of my two is this — simply does not arise here, and the sentence around it decides.