| Infinitismus | infinitism |
| Infantilismus | infantilism |
| Infinitiv | infinitive |
| Infinitivsatz | infinitive clause |
| infinitesimal | infinitesimal |
| Episitismus | predation |
| Spiritismus | spiritism |
| Fanatismus | fanaticism |
| Antinomismus | antinomianism |
| Nihilismus | nihilism |
| Infallibilismus | infallibilism |
| Infinität | uncertainty |
| Arminianismus | Arminianism |
| Binitarismus | binitarianism |
| Jainismus | Jainism |
| Leninismus | Leninism |
| Minimalismus | minimalism |
| Putinismus | Putinism |
| Trinitarismus | trinitarianism |
| Vaginismus | vaginismus |