Definition of "pièce de résistance" [piece de resistance]
A masterpiece; the most memorable accomplishment of one’s career or lifetime.(noun)
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Use "pièce de résistance" in a sentence
"The piece de resistance was a large green baize bag, which gave forth, as the old man restlessly lifted it from side to side, a charming jingle, as of innumerable golden guineas,"
"But Sam Lasko still had his piece de resistance to offer."