| SI | System of International Units (Systeme International D'unites) |
|---|---|
| BIPM | International Bureau of Weights and Measures [Fr. Bureau International des Poids et Mesures] |
| IAG | International Association of Gerontology; International Academy of Gnathology |
| IAP | immunosuppressive acidic protein; inosinic acid pyrophosphorylase; Institute of Animal Physiology; i... |
| IFA | idiopathic fibrosing alveolitis; immunofluorescence assay; immunofluorescent antibody; incomplete Fr... |