the solid layer of cement, bricks, stones etc that is put under a building to support it:
It took the builders three weeks to lay the foundations.
The earthquake shook the foundations of the house.
a basic idea, principle, situation etc that something develops from
All theories should be built on a foundation of factual knowledge.
The course gives students a solid foundation in the basics of computing.
an organization that gives or collects money to be used for special purposes, especially for charity or for medical research:
the British Heart Foundation
the establishment of an organization, business, school etc [= founding]:
The school has served the community since its foundation in 1835.
5 also have no foundation formal
if a statement, idea etc is without foundation, there is no proof that it is true [= be groundless]:
Davis dismissed the allegations as being without foundation.
to provide the conditions that will make it possible for something to be successful:
Careful planning laid the foundations for the nation's economic miracle.
a cream in the same colour as your skin that you put on before the rest of your make-up
8 also shake/rock something to its foundations
to completely change the way something is done or the way people think by having a completely new idea:
Darwin's theory rocked the scientific establishment to its foundations.