What is it called when the atmosphere absorbs things and it goes into the clouds?

I believe the answer you're looking for is:

Condensation- If the air cools, then water vapor molecules slow down and some can not remain a vapor. They cluster in the air to form tiny liquid droplets. This is called condensation. In clouds, the liquid droplets formed by condensation are small and light enough that they stay in the air.

hope this helps! :)