DI

la-di-da

1. adjective Pretentiously snobbish or elitist. I'd rather not go to some la-di-da restaurant and get overpriced rabbit food. Let's just get pizza.
2. interjection A sarcastic and derisive phrase meant to mock what one perceives as pretentious or overly refined. Well, la-di-da, look at Mr. Fancy in his new suit. Wow, you were on student council? La-di-da!
Farlex Dictionary of Idioms.

lah-di-dah

(ˈlɑˈdiˈdɑ)
1. mod. casual; relaxed and uncaring. She’s not all that calm about her possessions, but she is very lah-di-dah with men.
2. interj. a jeer; a mocking response. So you have a new car! Well, lah-di-dah.
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions
See also:
  • dah
  • la-di-da
  • lah
  • lah-di-dah
  • not anything to boast about
  • bulletproof
  • appropriate for
  • stuck-up
  • artsy
  • nothing to boast about