Longman Dictionary of Contemporary English
The Collaborative International Dictionary
Wiktionary
a. Moderately formal; usually requiring a dinner jacket (tuxedo) for men.
WordNet
adj. moderately formal; requiring a dinner jacket; "he wore semiformal attire"; "a black-tie dinner" [syn: semiformal, semi-formal]
Usage examples of "black-tie".
The family usually wore black-tie for holiday meals, but no one could quite envision stumbling out to the biffy in satin pumps, so orders had gone out not to bring formal clothes.
You may think of the theater as being sophisticated and artsy, but our roots are in traveling troupes that were closer to carnivals and snake-oil shows than any black-tie opening night.
After a high-profile black-tie affair in the ballroom of a Washington hotel, the Soviet ambassador had discovered a picture postcard in his coat pocket as his limousine returned him to the embassy.
Harper Stokes's confession of healthcare fraud that he would casually drop at his daughter's black-tie event, high on vodka tonics and friends.