fundamental law

American  

noun

1. the organic law of a state, especially its constitution.

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fundamental law British  

noun

1. the law determining the constitution of the government of a state; organic law

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Etymology

Origin of fundamental law

First recorded in 1910–15

Example Sentences

The mattering instinct “implicates both the most fundamental law of the science of matter, the law of entropy,” as well as “the biological imperative to resist it.”

From The Wall Street Journal • Jan. 9, 2026

The word itself, mend and amend, which have the same roots, testified to something that I really believe in about people, about political orders, about fundamental law: That things can be made better.

From Slate • Sep. 8, 2025

A similar attempt to change the fundamental law failed in 2019 because turnout was below a required 50% of registered voters to be valid.

From Seattle Times • May 9, 2024

“A constitution is in fact a fundamental law or basis of government, and falls strictly within the definition of law as given by Mr. Justice Blackstone,” Story writes.

From Salon • Dec. 16, 2023

It is a fundamental law of Nature, as basic as gravity.

From "Cosmos" by Carl Sagan