Dewpoint Defined by Bob Cobe,

I have finally come up with an intelligent definition of "dewpoint" and thought this might benefit everyone.

Dewpoint is the temperature at which air holds all the water vapor it can possibly contain. If the temperature drops below dewpoint, the air must "give up" water vapor in the form of condensation.
Refrigerant dehumidifiers operate on the principle of dewpoint.
Moisture-laden air passes over cold evaporator coils. The cold coils lower the temperature of the air below its dewpoint. Moisture condenses on the coils and drains into the pan to be pumped out.