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