| Abbreviation | Definition |
|---|---|
| CIDI | Christians in Defense of Israel |
| CIE | Christian International Embassy |
| CIFC | Christian Inter Fellowship Council |
| CIG | Communauté Israélite de Genève |
| CIIB | Cultural Interchange Institute for Buddhists |
| CIIR | Catholic Institute for International Relations |
| CIL | Communauté Israélite de Lausanne |
| CILV | Communauté Israélite de Lausanne et du canton de Vaud |
| CIMN | Christian International Ministries Network |
| CIN | Catholic Information Network |
| CINO | Catholic in Name Only |
| CINO | Christian in Name Only |
| CIRC | circumcision |
| CIRF | Center for Islam and Religious Freedom |
| CIS | Christians In Science |
| CISA | Catholic Information Service for Africa |
| CISCO | Christian Infrastructure Serving Communities |
| CISD | Center for Interfaith Studies and Dialogue |
| CIST | Christians in Schools Trust |
| CISU | Congregation Israelite Sepharade Unifiee |