Plain English Meaning
Flying by looking outside. The pilot keeps the airplane level and on course by watching the horizon and the ground, not by reading the instruments.
Full Definition
Flight in which the pilot controls the airplane's attitude and flightpath primarily by reference to the natural horizon and other outside visual cues, rather than by reference to cockpit instruments.
Context Anchor
In instrument training, this term appears when comparing normal outside-reference flying with flying by reference to instruments.
Derivation
Visual comes from the Latin word videre, meaning “to see.” In visual flight, seeing outside the airplane is the main way the pilot judges and controls the airplane.