• 1. a mass of water or ice particles visible in the sky, usually white or grey, from which rain or snow falls when the particles coagulate - See also cirrus cumulonimbus cumulus stratus
• 2. any collection of particles visible in the air, esp of smoke or dust
• 3. a large number of insects or other small animals in flight
• 4. something that darkens, threatens, or carries gloom
• 5. a cloudlike blemish in a transparent stone
• 6. to make or become cloudy, overcast, or indistinct
• 7. to make obscure;...

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