1. came into violent contact; collided forcefully
2. disagreed strongly; had a serious argument or conflict
3. made a loud, harsh metallic sound when struck together

Examples

• The two cars clashed at the intersection.
• The protesters clashed with police outside the building.
• The cymbals clashed loudly during the orchestra performance.
• Her bright orange shirt clashed with her red pants.
• The rival gangs clashed in the street.
• The metal gates clashed shut behind them.
• Their opinions clashed on every major issue.