1. a person who acts in a foolish or stupid way
Usage: informal; can be offensive
2. a person with severe intellectual disability
Usage: archaic; medical; now considered offensive

Examples

• Don’t be an idiot – wear your seatbelt!
• I felt like such an idiot when I locked my keys in the car.
• Only an idiot would try to fix electrical wiring without turning off the power.
• He called himself an idiot for forgetting his wallet at home.
• The movie portrayed the villain as a complete idiot who couldn’t do anything right.
• She realized she had been acting like an idiot and apologized.