noun, feminine/ʃa.ʁɛt/plural: charrettes
charette (small two-wheeled cart); period of intense work (to meet a deadline)
“être charrette” — to drown in work
From Middle French charrete, from Old French charrete; from char + -ete (diminutive). Sense “period of intense work” probably from architecture students loading their work into a cart (pulled by the youngest member) on the day of an exposition.