Idiom meaning, usage examples, facts

1. John told Robert about the job he was planning to apply for and Robert went out and got it himself! Robert doesn’t play fair. He hits below the belt.
2. Mary introduced Sally to her boyfriend, Mike, and before she knew it, Sally and Mike were dating. That was below the belt.

The expression originates from the sport of boxing, in which it is against the rules to hit one’s opponent below his or her belt.