Category Nuances for stock-market_crash:

• economic,
• singular,
• critical,
• unpredictable,
• financial,
• rare,
• complex,
• dramatic,
• sudden,
• single,
• catastrophic,
• untoward,
• systemic,
• seminal,
• repeated,
• historical,

Simple Categories for stock-market_crash:

• event,
• catastrophe,
• change,
• disaster,