| IS | a narrow isthmus linking the Malay Peninsula to the Asian mainland |
|---|---|
| IS | the isthmus that connects Central America and South America |
| IS | the isthmus in northeastern Egypt that connects Africa and Asia |
| IS | 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 |
| IS | sailfishes |
| IS | type genus of the Istiophoridae |
| IS | a kind of sailfish |
| IS | drug (trade name Isuprel) used to treat bronchial asthma and to stimulate the heart |
| IS | in some classifications another name for the family Lamnidae |
| IS | mako sharks |
| IS | common blue-gray shark of southwest Pacific |
| IS | very swift active bluish shark found worldwide in warm waters |