Plain English Meaning
Tiny dry particles floating in the air that make it harder to see clearly into the distance, even when the air feels dry.
Full Definition
A suspension of fine, dry particles (such as dust, smoke, or salt) in the lower atmosphere that reduces visibility by scattering light. Haze typically gives the air a milky, opalescent, or yellowish appearance and is distinct from fog or mist, which involve suspended water droplets.
Context Anchor
Pilots encounter haze in weather reports, preflight planning, and especially during night flying when outside visual references may be faint or blurred.
Derivation
From an English word of uncertain origin recorded since the 1700s, originally describing a hazy or obscured appearance of the sky. Knowing the word has always pointed to atmospheric obscuration helps separate it from related terms like fog or smoke.