underlying
v.v. hidden or not obvious, but very important for explaining why something happens. It describes the real cause or foundation of a situation.
v. situated beneath the surface; fundamental or primary, though not immediately apparent. Often used to describe root causes in economic or psychological contexts.
The underlying problem is a lack of communication.
Economists are worried about the underlying inflation rate despite the recent drop in energy prices.
While the surface-level symptoms were treated quickly, the underlying structural weaknesses in the banking system remained unaddressed for several years.
By surface analysis, underlie + -ing.
Typically placed before the noun it modifies; frequently used in academic and financial registers to discuss root causes.