Index - O
| Oboe | EuterpeaUtils |
| Ocarina | EuterpeaUtils |
| Octave | |
| 1 (Type/Class) | Types |
| 2 (Type/Class) | EuterpeaUtils |
| offset | EuterpeaUtils |
| onsets | Types |
| ontime | Types |
| OpenCuica | EuterpeaUtils |
| OpenHiConga | EuterpeaUtils |
| OpenHiHat | EuterpeaUtils |
| OpenTriangle | EuterpeaUtils |
| OrchestraHit | EuterpeaUtils |
| OrchestralHarp | EuterpeaUtils |
| orderedResults | Analysis |
| Orn | EuterpeaUtils |
| Ornament | EuterpeaUtils |
| OverdrivenGuitar | EuterpeaUtils |