MDBG: one stumble, unable to rise (idiom); a setback leading to total collapse; ruined at a stroke; unable to recover after a minor hitch
LDC:
CDict: '
Click icons for complete source definitions (not available on mobile). icon in each entry gives source attribution. Want to improve this definition? Check to see if 一蹶不振 is already in CC-CEDICT. If not, you can add it. (Why?)