- Obsessed Adj
- Obsessional Adj
- Obsessive Adj Noun
- Obsidional Adj
- Obsignatory Adj
- Obsolescent Adj
- Obsolete Adj Verb
- Obstetric Adj
- Obstetrical Adj
- Obstinate Adj
- Obstipated Adj
- Obstipating Adj
- Obstreperous Adj
- Obstructed Adj
- Obstructionist Adj Noun
- Obstructive Adj
- Obstruent Noun Adj
- Obtainable Adj
- Obtained Adj
- Obtrusive Adj
- Obtundent Adj Noun
- Obturated Adj
- Obturating Adj
- Obturative Adj
- Obtuse Adj
- Obverse Adj Noun
- Obvious Adj
- Obvolute Adj
- Occasional Adj
- Occidental Adj Noun
- Occidentalised Adj
- Occipital Adj Noun
- Occipitoanterior Adj
- Occipitocervical Adj
- Occipitofacial Adj
- Occipitofrontal Adj
- Occipitomastoid Adj Noun
- Occipitomental Adj
- Occipitoparietal Adj
- Occipitotemporal Adj
- Occipitotrigeminal Adj
- Occitan Adj Noun
- Occluded Adj
- Occluding Adj
- Occlusal Adj
- Occlusive Adj Noun
- Occult Adj Noun Verb
- Occulted Adj
- Occupational Adj
- Occupative Adj
- Occupiable Adj
- Occupied Adj
- Occurrent Adj Noun
- Oceanfront Adj Noun
- Oceangoing Adj
- Oceanian Adj Noun
- Oceanic Adj
- Oceanographic Adj
- Oceanographical Adj
- Oceanological Adj