[Fr.] A phrase used as an adj. in sense: Pertaining to, or characteristic of, the end of the (nineteenth) century; characteristically ‘advanced’ or modern.

1

1800.  Daily News, 29 Dec., 2/2. The finance of the year has been special—fin de siècle.

2

1891.  Melbourne Punch, 4 June, 377/1. The fin de siècle ballet.

3