culottes n.

ballet skirt, 1910, from French tutu, alteration of cucu, infantile reduplication of cul "bottom, backside," from Latin culus "bottom, backside, fundament," from PIE *kuh-lo- "backside, rear" (source also of Old Irish cul "back," Welsh cil "corner, angle"), ultimate origin obscure [de Vaan].

also sans-culotte, "lower-class republican of the French Revolution," 1790, from French, literally "without breeches;" see sans + culottes. This usually is explained as referring to the whose distinctive costume was pantalons (long trousers) as opposed to the upper classes, which wore culottes (knee-breeches), but this is not certain. Whatever the origin, the name was embraced from the start by the revolutionists of Paris. Related: Sansculottes; sansculotterie; sansculottic; sansculottism. "opinions and principles of the sancullotes."

Unhappy Friends of Freedom ; consolidating a Revolution ! They must sit at work there, their pavilion spread on very Chaos ; between two hostile worlds, the Upper Court-world, the nether Sansculottic one ; and, beaten on by both, toil painfully, perilously,—doing, in sad literal earnest, 'the impossible.' [Carlyle, "The French Revolution"]