basement complex

American  

noun

Geology.

1. the undifferentiated assemblage of rock basementrock underlying the oldest stratified rocks in any region: usually crystalline, metamorphosed, and mostly, but not necessarily, Precambrian in age.

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Etymology

Origin of basement complex

First recorded in 1895–1900

Example Sentences

By 2:30 p.m., police ordered a full evacuation to secure rooms outside the Capitol, prompting an underground race through the basement complex.

From Washington Post

I failed to uncover either critical Republican senator during numerous strolls through the winding basement complex that I took throughout the day, but found Collins’ spokeswoman and asked if her boss would be coming through too.

From Slate

Williams wants to put in a basement complex which will come perilously close to Tower House.

From The Guardian

Erosion has laid bare portions of the earth's crust which were once deeply buried, and reveals the character of the "basement complex," as it has been termed, which forms the foundation of the continent.

From Project Gutenberg

Deep, 20.Basement complex, 310.Bay of Fundy, tides in, 29.Bear,

From Project Gutenberg