zero hour

a time or state of affairs requiring prompt or decisive action we're at the zero hour, so someone has to make a decision Synonyms boiling point, breaking point, clutch, conjuncture, crisis, crossroad(s), crunch, crunch time, Dunkirk, exigency, extremity, flash point, head, juncture, tinderbox, emergencyRelated Words contingency, possibility; climax, turning point; happening, landmark, milestone; condition, pass, situation, strait; deadlock, impasse, stalemate; corner, fix, hole, hot water, jam, last ditch, pinch, predicament, scrape, spot; eleventh hour, last minute