I felt very bad because here was the man I liked and trusted the most as a critic then, the man who believed in the mot juste—the one and only correct word to use—the man who had taught me to distrust adjectives as I would later learn to distrust certain people in certain given situations...
-- Ernest Hemingway, A Moveable Feast, 1964
I felt that something might be learned of what I wanted from Flaubert and the mot juste so admired by Ford and Pound.
-- A. S. Byatt, "Still Life/nature morte," Passions of the Mind, 1991
Mot juste is a borrowing from the French word of the same spelling and meaning. It entered English in the late 1800s.