Very formal; usually requiring a tailcoat for men.(adjective)
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Use "white-tie" in a sentence
"The shop recently supplied the black- and white-tie shirts for Hugh Bonneville's character Robert, Earl of Grantham, in the television series "Downton Abbey.""
"The typically stiff white-tie crowd erupted in cheers when wheelchair-bound Swedish poet Tomas Transtromer, partially paralyzed by a stroke two decades ago, received the Nobel Prize in literature."
"They escorted her to the annual Master of Foxhounds Ball in New York, the white-tie dances for hunt clubs."