warp and woof

n.
The underlying structure on which something is built; a base or foundation: "profound dislocations throughout the entire warp and woof of the American economy" (David A. Stockman).

noun

A distinctive, complex underlying pattern or structure: contexture, fabric, fiber, texture, web. See be.

The underlying structure or foundation of something, as in He foresaw great changes in the warp and woof of the nation's economy. This expression, used figuratively since the second half of the 1500s, alludes to the threads that run lengthwise ( warp) and crosswise (woof) in a woven fabric.

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