**loop**. **1** lokaður ferill, lokaður vegur, lykkja, = *circuit 1*, = *closed contour*, = *closed curve*, = *closed line*, = *closed path*, = *contour 1*. **2** (*in algebra*) lúpa. **3** (*in graph theory*) snara, = *self loop*.

**loop space** lykkjurúm.

**looping coefficient** hlekkjunartala, = *linking number*.