"System D (in French, Système D) is a shorthand term that refers to a manner of responding to challenges that requires one to have the ability to think fast, to adapt, and to improvise when getting a job done. The letter D refers back to either of the French nouns "débrouille",[1] débrouillardise[2] or démerde (French slang). The verbs se débrouiller and se démerder mean to make do, to manage, especially in an adverse situation."