| IST | the largest city and former capital of Turkey |
|---|---|
| IST | of or relating to or forming an isthmus |
| IST | ancient games held biennially on the Isthmus of Corinth in the first and third years of each Olympiad |
| IST | a narrow band of tissue connecting two larger parts of an anatomical structure |
| IST | a relatively narrow strip of land (with water on both sides) connecting two larger land areas |
| IST | a narrow isthmus between the Gulf of Corinth and the Saronic Gulf |
| IST | a narrow isthmus linking the Malay Peninsula to the Asian mainland |
| IST | the isthmus that connects Central America and South America |
| IST | the isthmus in northeastern Egypt that connects Africa and Asia |
| IST | the narrowest part of southern Mexico is an isthmus between the Bay of Campeche on the north coast and the Gulf of Tehuantepec on the south coast |
| IST | sailfishes |
| IST | type genus of the Istiophoridae |