| Hypocritical | insincere |
| Iconoclast | person who opposes orthodoxy |
| Idiosyncrasy | a personal peculiarity; something unique to an individual |
| Ignominious | shameful |
| Ignominy | shame [ignominious (a) = shameful] |
| Illuminate | to light up or make clear |
| Illusory | deceptive; false; misleading |
| Immoderate | excessive; extreme |
| Immutable | unchanging; permanent |
| Impartial | unbiased; neutral |
| Impecunious | having no money |
| Impious | wicked; profane |
| Impoverished | destitute; poor |
| Impromptu | unrehearsed; spontaneous |
| Inadvertent | not intentional |
| Incantation | chant; invocation; prayer |
| Incarceration | putting in prison |
| Incessant | without stopping |
| Incipient | just beginning |
| Inclination | tendency; a leaning toward |
