Crepitus: A clinical sign in medicine characterized by a peculiar crackling, crinkly, or grating feeling or sound under the skin, around the lungs, or in the joints.

Crepitus in soft tissues is often due to gas, most often air, that has penetrated and infiltrated an area where it should not normally be, as for example the soft tissues beneath the skin (a condition called subcutaneous emphysema). Crepitus in a joint can represent cartilage wear in the joint space.

The term "crepitus" is taken directly from the Latin "crepitus" meaning "a crackling sound or rattle."