| Label | Id | |
|---|---|---|
| old age | Age | |
| older age | Age | |
| older family members | Species | |
| Old k-chest | Disease | |
| olfactory epithelium | Biological | |
| once a day | Times | |
| once daily | Times | |
| On cells | Condition | |
| ongoing infectious | Severity | |
| organ dysfunction | Disease | |
| organ lesions | Disease | |
| other countries | Area | |
| other proteolytic enzymes | Problem | |
| other symptoms | Disease | |
| over-exuberant cytokine release | Problem |