Plain English Meaning

Three tiny tubes of fluid in your inner ear that detect when your head turns or tilts. They are how your body normally knows you are rotating.

Full Definition

Three small, fluid-filled loops inside the inner ear, arranged at right angles to one another, that sense rotational movement of the head. Movement of fluid within the canals stimulates tiny hair cells, which send signals to the brain about angular motion in roll, pitch, and yaw.

Context Anchor

Encountered in discussions of airplane feel, balance, motion sensing, and why pilots must rely on instruments when outside visual references are poor.

Derivation

From Latin 'semi' (half) and 'circularis' (circular), describing their half- shape. The name simply reflects what the canals look like — curved loops rather than complete rings.