"wavy ornamental edging," 1801 (with a doubtful attestation from 1590s), of uncertain origin despite much speculation [see OED]; figurative sense of "useless ornament" first recorded 1893. Related: Frills.
word-forming element making nouns meaning "place for, art of, condition of, quantity of," from Middle English -erie, from Latin -arius (see -ary). Also sometimes in modern colloquial use "the collectivity of" or "an example of."
<a href="https://www.etymonline.com/word/frillery">Etymology of frillery by etymonline</a>
Harper, D. (n.d.). Etymology of frillery. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/frillery