There are many words that people often mispronounce when they say them aloud, because they know them only from reading. Cache (pronounced "kash") and cachet (rhymes with "sashay") fall into this category. Radio reports sometimes mention "weapons caches" – and pronounce it "ka-SHAYS." Oops!
Conversely, I've seen in print comments to the effect that this or that business school, for instance, has "great cache" or even "caché." Cache and cachet seem to pop up in each other's place like twins continually mistaken for each other in a Shakespearean comedy.
Just to be clear: Cache is a hiding place for food, ammunition, or similar supplies, or the supplies themselves. It has often been spelled the way it's been pronounced. Cache is associated particularly with explorers of the American West – Lewis and Clark, for instance – and the Arctic.
A cachet, on the other hand, was originally a seal – a king's personal seal, as distinct from an official seal. Then the meaning stretched to cover any indication of approval conveying great prestige (e.g., "Istvan's new place has won the cachet of the Best of Boston award for the Best New Afghan-Hungarian deli").
From there cachet has come to refer to the prestige itself.
Cachet has its very dark side, though. A letter of cachet (lettre de cachet, in French) was a letter by the French king, under his private seal (going back to that original meaning of cachet) containing an order, often for someone's imprisonment or death.
A happier specialized use of cachet is a philatelic one – the little advertising message or other motto on a postmark or a postage meter impression, "Season's Greetings" or whatever.
If there seems to be a family resemblance between cache and cachet, are the two words related? Yes. Both derive from the French word cacher, to hide.
But cache and cachet, like twins separated at birth, have gone off on different paths. Cache started out as a hiding place for supplies, then became a hidden supply of something, and more recently has become a not-so-hidden supply.
Cachet, on the other hand, started as the personal seal, the one that was more or less hidden. But the part of cachet that developed was not its "hidden" quality but its connection with high-level approval.
Omnibus comes to mind as another example of widely divergent meanings springing from a single root. Omnibus is Latin and means "for all." In the 19th century it was applied to public conveyances – those providing "carriage for all." The word was shortened to "bus" and then applied to all manner of carts and conveyances.
But legislators often speak of "omnibus bills" – those with something for everyone, aka "Christmas tree bills." The emphasis is on the "everyone" rather than the transport, and "omnibus" is not abbreviated.
Fortunately bus and omnibus cause no particular pronunciation problems. Confusions over cache/cachet, on the other hand, are often the mark of the autodidact, who learns from his or her own reading but then may not get a chance to discuss it.
My own high-water mark in this regard came some years ago as I was getting ready to do a television interview in which I was to discuss the work of psychologist Mihaly Csikszentmihalyi. As a production assistant was going through the ticklish business of running microphone wires through my sleeve, it suddenly dawned on me that for all the time I spent reading Csikszentmihalyi's book, I really wasn't sure how to pronounce his name.
Fortunately, a slightly panicked call to his publisher's publicists settled the confusion. Thank goodness for publicity departments.
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