Use the noun frock as an old-fashioned way to say "dress." You might wear a new pinkfrock to your best friend's birthday party.

Pronunciation: /frɔk/
English Description: a woman's or girl's dress or a long loose piece of clothing worn by some Christian monks.
Chinese Translation: 上衣(Shang4 Yi1)，罩袍(Zhao4 Pao2)
Spanish Translation: vestido largo de mujer
STORY: Typically, girls and women wear frocks, especially to formal events like weddings and fancy parties. The word frock isn't as common today as it was in the past, though it's a great way to refer to a dress. You can also call a monk's loose, long-sleeved garment a frock. The word's origin is Germanic, and it comes directly from the French word froc, "a monk's habit."

EXAMPLE SENTENCE:

WSPU members wear their official uniforms of a white frock decorated with purple, yellow and green accessories.

P.S: New word description, story and part of "EXAMPLE SENTENCE" are cited in Vocabulary.com