| notable(extraordinary, unusual, wonderful, exceptional, special) |
| noteworthy(unusual, special, rare) |
| obscure(strange, isolated, indefinite, reclusive, uncompanionable) |
| oddball(odd, bizarre, outlandish) |
| off(odd, bizarre, outlandish) |
| off beaten track(expression, adjective, idiom, wonderful, isolated) |
| offbeat(adjective, extraordinary, unusual, exceptional, odd) |
| original(unusual, special, rare) |
| orphic(isolated, reclusive, uncompanionable) |
| out-of-the-way(odd, bizarre, outlandish) |
| out of earshot(expression, idiom, isolated, reclusive, uncompanionable) |
| out of range(expression, idiom, isolated, reclusive, uncompanionable) |
| out of reach(expression, idiom, isolated, reclusive, uncompanionable) |
| out of the way(expression, idiom, unusual, special, rare) |
| out of view(expression, idiom, isolated, reclusive, uncompanionable) |
| outlandish(odd, bizarre) |
| outre(adjective, unusual, special, rare, uncommon) |
| outstanding(light, thin, unusual, special, rare) |
| paper-thin |
| peaky |