| Term | Definition |
| notorious (adj) | outstandingly bad; unfavorably known |
| novelty (n) | something new; newness |
| novice (n) | beginner |
| noxious (adj) | harmful |
| nuance (n) | shade of difference in meaning or color |
| nullify (v) | to make invalid |
| nurture (v) | bring up; feed; educate |
| obdurate (adj) | stubborn |
| obfuscate (v) | confuse; muddle |
| obligatory (adj) | binding; required |
| oblique (adj) | slanting; deviating from the perpendicular or from a straight line |
| obliterate (v) | destroy completed |
| oblivion (n) | forgetfulness |
| obscure (adj) | dark; vague; unclear |
| obsequious (adj) | slavishly attentive, servile, sycophancy |