Labium is the Latin word for
lip. In English, it may refer to:
- Labia, a part of the female external genitalia
- Labium (botany), a modified petal in certain monocot flowers, which attracts insects for pollination
- Labium (arthropod mouthpart), a mouthpart of arthropods (the lower "lip")
- Labium (wasp), a genus of wasps in the family Ichneumonidae
- Labium (wind instrument), a part of wind instruments such as the recorder, see fipple