Plain English Meaning

It is your inner-ear sense of balance and motion. It tells your brain which way is up, whether you are turning, and whether you are speeding up or slowing down. In an airplane, this sense is easily fooled.

Full Definition

The sense of balance, motion, and body position generated by the vestibular system of the inner ear, which detects linear acceleration, angular acceleration, and the pull of gravity. In flight, this sense can be misled by sustained turns, accelerations, and the absence of outside visual references, producing spatial disorientation.

Context Anchor

Seen in discussions of spatial disorientation and maintaining airplane control in darkness, clouds, haze, or any where the outside is to see.