n.1 a the solid ground or base, natural or artificial, on which a building rests. b (usu. in pl.) the lowest load-bearing part of a building, usu. below ground level.
2 a body or ground on which other parts are overlaid.
3 a basis or underlying principle; groundwork (the report has no foundation).
4 a the act or an instance of establishing or constituting (esp. an endowed institution) on a permanent basis. b such an institution, e.g. a monastery, college, or hospital.
5 (in full foundation garment) a woman's supporting undergarment, e.g. a corset.
Phrases and idioms:
foundation cream a cream used as a base for applying cosmetics. foundation-stone
1. a stone laid with ceremony to celebrate the founding of a building.
2 the main ground or basis of something.
Derivatives:
foundational adj.
Etymology: ME f. OF fondation f. L fundatio -onis (as FOUND(2))