lah-de-dah

variants or lah-dee-dah or lah-di-dah

less common spellings of la-di-da

informal

: affectedly or pretentiously elegant or refined in manners or tastes

… they soon became civilized. Two years later Fabyan saw them in Westminster Palace, dressed like la-di-da English courtiers.

—Samuel Eliot Morison

Iris was a freshman at Climping Academy, the Santa Teresa private school located in Horton Ravine, which was so la-di-da, it totally freaked her out.

—Sue Grafton