1. a person who betrays someone who trusts them
Usage: often capitalized when referring to the biblical figure
2. a small window or opening in a door used for looking out
Usage: also called judas hole

Examples

• He felt like a judas for revealing his friend’s secret.
• The company’s former employee turned judas and sold trade secrets to competitors.
• She looked through the judas to see who was at the door.
• The apartment door had a small judas for security purposes.
• His betrayal earned him the reputation of being a judas among his colleagues.
• The old castle door featured an ornate judas with iron bars.