Glyndebourne

In British usage, Glyndebourne functions as shorthand for the famous opera festival held at Glyndebourne House in East Sussex, England. Saying someone 'went to Glyndebourne' instantly communicates high culture, upper-middle-class social life, and the specific British tradition of dressing in evening wear, bringing a hamper, and eating a picnic on the lawn during the long interval. It's one of those words that carries enormous cultural weight — invoking champagne, summer gardens, and very expensive tickets — in a way that just saying 'opera' wouldn't capture.