| Int | Rot internal rotation |
|---|---|
| IO | incisal opening; inferior oblique; inferior olive; internal os; interorbital; intestinal obstruction... |
| IQAS | internal quality assurance system |
| IRE | internal rotation in extension; iron-responsive element; isolated rabbit eye |
| IRF | idiopathic retroperitoneal fibrosis; impulse response function; interferon regulatory factor; intern... |