Relating to or characteristic of a type of clay mineral with a layered structure and the ability to swell when it absorbs water.
The word smectitic is used in geology and soil science to describe a specific type of clay mineral.
Examples:
The smectitic clay can swell when it absorbs water.
The smectitic mineral has a layered structure.
The smectitic soil is good for growing plants.
The smectitic clay is like magic when it absorbs water!
The smectitic mineral is the best for making pottery.
The smectitic soil is so special because it can hold a lot of water.