1. a baseball pitch that curves as it approaches the batter
Usage: baseball
2. an unexpected problem or surprise that disrupts plans
Usage: informal

Examples

• The pitcher threw three curveballs in a row.
• His curveball drops sharply just before reaching home plate.
• Life threw us some curveballs this year.
• The new regulations were real curveballs for the company.
• She handled all the curveballs with grace.
• The test had several curveballs that caught students off guard.
• Nobody expected those curveballs during the meeting.