base level

American  

noun

Geology.

1. the lowest level to which running water can erode the land.

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base level British  

noun

1. the lowest level to which a land surface can be eroded by streams, which is, ultimately, sea level

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Etymology

Origin of base level

First recorded in 1870–75

Example Sentences

Like Microsoft, Amazon did not specify the base level sales figure its chips business run-rate was calculated on.

From BBC • Apr. 29, 2026

"That was the idea: to create confusion and generate skepticism at the base level by distorting certain elements of real things."

From Barron's • Jan. 20, 2026

“Boiled down to the base level, yeah, you kick a ball through the pipes,” said Dicker, 25, whose team plays host Sunday to the Indianapolis Colts.

From Los Angeles Times • Oct. 17, 2025

At a base level, buildings are fortified with thicker beams, pillars, and walls to better withstand shaking.

From National Geographic • Jan. 4, 2024

“If you’d died, that would’ve been a black mark on my reputation, so yes, at some base level, I was...worried.”

From "Aru Shah and the End of Time" by Roshani Chokshi