0 support, strength, or the basic structure of something:
After a while, we found ourselves questioning the spiritual and philosophical underpinning of the American way of life.
He has the capacity to understand the theoretical underpinnings that affect action.
1 something that provides support for something, or that is the starting point from which something can develop:
She is convinced that autism has biological underpinnings.
Some material might not be hot enough to melt steel underpinnings of a building.
