Green’s Dictionary of Slang

(Aus./US) ostentatious, pretentious.

1905		Sun. Times (Perth) 7 May 1/1: A Guildford girleen has landed the love and lucre of the eminent relic [and] Groperdom is unctuously anticipating the most frilly affair seen since the dookal visit.
1922		Adair Co. News (Columbia, KY) 3 Jan. 7/2: Is that so? — or is it only another one o’ his frilly lies?