| Deserter |
| Renegade |
| Turncoat |
| Faith forsaker |
| Faith abandoner |
| Former believer |
| One who's fallen |
| Religion renouncer |
| One who has lapsed |
| Religious defector |
| One who loses faith |
| Party switcher, say |
| Forsaker of the faith |
| Abandoner of the cause |
| Defector from the faith |
| Renouncer of one's faith |
| Someone who has abandoned their religion |