A suit consisting of matching jacket, trousers, and waistcoat.(noun)
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Use "three-piece suit" in a sentence
"Clean-cut, smart, like he ought have been wearing a three-piece suit and carrying a briefcase."
"It seemed the brothers had purchased every three-piece suit that was for sale: Black-and-white pin-stripes, blue-and-white pin-stripes, with fly-away collars and button-down jackets hiding matched silk vests accentuated by either Christian Dior or Calvin Klein ties."
"The driver, a stocky young woman of medium height dressed in a tweed three-piece suit and a little suède hat, got out, slammed the door, and came briskly up to George, who rose and saluted."