Look up thickness in Wiktionary, the free dictionary.
Thickness may refer to:
- Thickness (graph theory)
- Thickness (geology), the distance across a layer of rock
- Thickness (meteorology), the difference in height between two atmospheric pressure levels
- Thickness planer a woodworking machine
- Optical thickness in optics
- Thickness, a concept in the game Go
- Thickness of a fluid, an informal name for viscosity