A visible pall of air pollutants that persists over a city or other area: the Asian brown cloud throughout the day, air shifts in the valley cause variances in the brown cloud
More example sentences
- Today, that is all gone: no brown cloud, no atmospheric pollution to speak of.
- One look at the big brown cloud hanging perennially over Toronto and you know Rick Mercer is right: the first instinct is to run.
- Over everything hangs a brown cloud of pollution that is clearly visible from the hills outside the city.