The Collaborative International Dictionary of English v.0.48:
Jabot \Jab"ot\, n. [F.] 1. Originally, a kind of ruffle worn by men on the bosom of the shirt. [1913 Webster] 2. An arrangement of lace or tulle, looped ornamentally, and worn by women on the front of the dress. [1913 Webster]WordNet (r) 3.0 (2006):
jabot n 1: a ruffle on the front of a woman's blouse or a man's shirt