אֱדַ֤יִן מַלְכָּא֙ זִיוֺ֣הִי שְׁנ֔וֹהִי וְרַעיֹנֹ֖הִי יְבַהֲלוּנֵּ֑הּ וְקִטְרֵ֤י חַרְצֵהּ֙ מִשְׁתָּרַ֔יִן וְאַ֨רְכֻבָּתֵ֔הּ דָּ֥א לְדָ֖א נָֽקְשָֽׁן׃
Rashi on Daniel
and the belts of his loins became untied The belts of his loins opened because his loins were emptying out of fear, and his belt opened.