Parler français comme une vache espagnole

Literally: To speak French like a Spanish cow

Example: “Le touriste parlait français comme une vache espagnole, mais tout le monde l'a compris.” — The tourist spoke terrible French, but everyone understood him.

Origin: Attested by 1640, and the cow is probably an accident. The tidiest theory has vache as a corruption of basque, since 17th-century French wrote vasces or vasque for a Gascon or a Basque, and a Basque from the Spanish side of the border had no particular reason to speak good French — a variant runs the other way, parler français comme un Basque parle l'espagnol, on the grounds that Basques on either side of the Pyrenees were attached to their own language above the national one. A second theory derives it from basse, an obsolete word for a maidservant, on the assumption that the servants were Spanish and their French imperfect; the word left so few traces that this is hard to test. Alain Rey's account is the least tidy and the most likely: no corruption at all, just two insults stacked. A vache was then, and remains, a strongly pejorative intensifier, and espagnol was itself an insult at the time — payer à l'espagnole meant to pay someone in blows, and a piece of bragging was an espagnolade. The same pairing turns up in il est sorcier comme une vache espagnole, meaning a hopeless incompetent. Two nasty words about a way of speaking, and the cow was never the point.