Bedrock (noun)

1. The solid rock that lies beneath soil, sand, or other superficial deposits and forms the foundation of the earth.
2. The fundamental principles or basis on which something is constructed or established.

Origin:

From the combination of the words "bed" and "rock".

Examples:

1. The geologist studied the different layers of bedrock.
2. The miners had to blast through the bedrock to reach the coal.
3. The Bedrock is the foundation of the earth's surface.
4. The company's success was built on a strong bedrock of customer service.
5. The bedrock of our democracy is the right to vote.