Drier (adjective): A term used to compare the relative dryness of something. Specifically, this word indicates that something is less wet than the object to which it is being compared.
Dryer (noun): A machine used to dry something that is wet (e.g., hair), using heat or air movement.
Example Sentences: The glue has to be drier before you can touch it. Don't put wool in the dryer because it will shrink.