Double entendre sounds French, but the French never used it that way
The phrase we borrow for a cheeky second meaning is itself a kind of trick. It comes from an old French expression that simply meant ambiguity, and it only picked up its suggestive edge in English after John Dryden used it in 1673. Modern French has no exact equivalent.
A double entendre is wording built to carry two meanings at once: one plain, the other usually something too rude or awkward to say outright. It works through puns, words with several senses, homophones or deliberately planted ambiguity. Pack in three readings and you have a triple entendre, like the cover of Rush's 1981 album Moving Pictures, where movers carry paintings, onlookers are emotionally moved and a film crew records the scene.
According to Merriam-Webster and the Oxford English Dictionary, the source is a rare French phrase long since dropped from that language, and it would now be ungrammatical there. The nearest French terms, double entente and double sens, lack the English version's wink. Part of the appeal is exclusion: listeners who miss the hidden meaning may only notice others laughing, which is why sitcoms lean on innuendo that sails over some viewers' heads.
The device is ancient. In Homer's Odyssey, the captured Odysseus tells the Cyclops Polyphemus that his name is Oudeis, meaning No-one. After Odysseus blinds him, Polyphemus shouts that No-one has hurt him, so the other Cyclopes assume an accident and do nothing, letting the Greeks escape. England's 10th-century Exeter Book, kept at Exeter Cathedral, holds riddles whose answers were never written down; scholars have worked them out, and one famously describes something that makes a woman's eyes water and turns out to have the innocent answer an onion.
Chaucer's Wife of Bath, in the 14th-century Canterbury Tales, peppers her speech with sly wordplay, using a term for domestic chores that also meant something far earthier. Thomas More's Utopia of 1516 hides a pun in its very title: read one way the Greek roots mean no place, while a spelling that sounds identical in English would mean good place.
Source: Double entendre
