1. to interfere with something in a way that causes damage or makes unauthorized changes

Examples

• Someone had tampered with the lock on the door.
• The evidence showed that witnesses had been tampered with.
• Don’t tamper with the electrical wiring without proper training.
• The security seal will show if anyone has tampered with the package.
• It’s illegal to tamper with a jury during a trial.
• The mechanic discovered that someone had tampered with the brakes.