1. the absence or rejection of religious belief or practice
2. indifference or hostility toward religion

Examples

• The survey showed a growing trend toward irreligion among young adults.
• His irreligion was evident in his complete disregard for religious holidays.
• The philosopher wrote extensively about irreligion and secular ethics.
• She attributed her irreligion to her scientific education.
• The country’s constitution protects both religion and irreligion equally.
• His family struggled to accept his irreligion after years of devout practice.