Atmospheric moisture or dust or smoke that causes reduced visibility WordNet 3.0 & Open English WordNet

Haze is traditionally an atmospheric phenomenon in which dust, smoke, and other dry particulates suspended in air obscure visibility and the clarity of the sky. Wikipedia

Atmospheric phenomenon. Wikipedia Disambiguation

An atmospheric phenomenon where dry particles obscure the clarity of the sky Wikipedia Disambiguation

Atmospheric phenomenon in which dust, smoke, and other dry particulates obscure the clarity of the sky Wikidata

Meteorologic phenomenon consisting of a big number of dry and extremely small particles (dust, sand, smoke) in suspension and carried by the air, so that visibility is considerably reduced (aprox. between 1 and 5 kms). It occurs when the relative humidity is below 70-80%. It has an opalescent color. OmegaWiki

Very fine solid particles (smoke, dust) or liquid droplets (moisture) suspended in the air, slightly limiting visibility. Wiktionary

Very fine particles suspended in the air. Wiktionary (translation)