Crash1  —v. 1 (cause to) make a loud smashing noise. 2 throw, drive, move, or fall with a loud smash. 3 (often foll. By into) collide or fall, or cause (a vehicle etc.) To collide or fall, violently; overturn at high speed. 4 collapse financially. 5 colloq. Gatecrash. 6 computing (of a machine or system) fail suddenly. 7 colloq. Pass (a red traffic-light etc.). 8 (often foll. By out) slang sleep, esp. On a floor etc. —n. 1 loud and sudden smashing noise. 2 violent collision or fall, esp. Of a vehicle. 3 ruin, esp. Financial. 4 computing sudden failure of a machine or system. 5 (attrib.) Done rapidly or urgently (crash course in first aid). —adv. With a crash (go crash). [imitative]