Even if you're an eminence grise who has fashioned a piece de resistance and mastered the lingua franca, you still might have trouble with these three foreign phrases:

— Eminence grise (AY-mee-nonce-GREEZ) — This expression, literally, "the gray eminence," refers to an influential adviser who functions as the power behind the throne. For the first few months of President Donald Trump's second presidency, some pundits used this term to describe Elon Musk.

Because such mentors are often wily veterans, most people assume the "grise" refers to their gray hair. Not so.

"Eminence grise" originated with Pere Joseph, the 17th-century Capuchin friar who served as confidante, counselor and secret agent to Cardinal Richelieu, chief minister of Louis XIII of France.

Because Richelieu wore a cardinal's red robe, he became known as "L'Eminence Rouge" ("the Red Eminence"). And, because Pere Joseph wore the gray habit of the Capuchin order, he was called "L'Eminence Grise" ("the Gray Eminence"). Eventually, "eminence grise" became a general term for any behind-the-scenes adviser.

But during the past 50 years, people have increasingly and erroneously associated "eminence grise" with gray hair. Today, this "elder statesman" connotation is so dominant that it might even seem odd to apply the term, quite correctly, to a rumpled-haired, disheveled wunderkind.

— Piece de resistance — Many people use this term to refer to the final achievement of a meal, performance or presentation — the capper or closer. Thus, they might use it for a chef's dessert or a gymnast's perfect landing simply because, chronologically, these were their final triumphs.

In fact, the "resistance" in "piece de resistance" refers to staying power, endurance — something of strength that will last. So the term should actually refer to the singularly outstanding item in a meal, performance or body of work, whether it occurs first, last or in between.

— Lingua franca — This term, literally "the Frankish tongue" in Italian, originally referred to a blend of Italian, French, Spanish, Greek and Arabic once commonly spoken in Mediterranean ports.

By extension, it has come to mean any language used to communicate among diverse groups. French, for instance, was once the lingua franca of diplomacy, and English is the lingua franca of international air travel.

But can "lingua franca" be used to describe non-linguistic communication?

Yes. One could say that rock music is the lingua franca of the world's youth.

Rob Kyff, a teacher and writer in West Hartford, Conn., invites your language sightings. His book, "Mark My Words," is available for $9.99 on Amazon.com. Send your reports of misuse and abuse, as well as examples of good writing, via e-mail to Wordguy@aol.com or by regular mail to Rob Kyff, Creators Syndicate, 737 3rd Street, Hermosa Beach, CA 90254.

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