white tie

(noun) bow tie worn as part of a man's formal evening dress. Synonyms: white tie.

(noun) formalwear consisting of full evening dress for men. Synonyms: dress suit, full dress, tailcoat, tail coat, tails, white tie, white tie and tails.

(adj) requiring white ties and tailcoats for men. Synonyms: white-tie. Example: "A white-tie occasion."