1. the solid base or support on which a building or structure is built
2. the basic principles or underlying facts that support or form the basis of something
3. an organization established to provide money for charitable, educational, or research purposes

Examples

• The workers poured concrete for the building’s foundation.
• Trust is the foundation of any good relationship.
• The foundation donated millions to cancer research.
• She studied the foundation of modern democracy.
• The foundation was established in 1985.
• She applied foundation before putting on her makeup.
• The house has a solid stone foundation.
• Reading skills are the foundation for academic success.