Gypsum (noun)

1. A soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula CaSO4·2H2O.
2. A white or grayish mineral, used to make plaster of Paris, fertilizer and other products.

Origin:

From the greek word "gypsos" meaning "chalk" or "plaster".

Examples:

1. The walls were made of gypsum.
2. Gypsum is used to make plaster of Paris.
3. Gypsum is a common mineral in sedimentary rocks.
4. The gypsum mines were a major source of employment.
5. The gypsum rock was crushed and used as a fertilizer.