Fundamental

a.	1.	Pertaining to the foundation or basis; serving for the foundation. The fundamental reasons of this war. - Shak. Some fundamental antithesis in nature. - Whewell. Fundamental bass (Mus.) the root note of a chord; a bass formed of the roots or fundamental tones of the chords. Fundamental chord (Mus.) a chord, the lowest tone of which is its root. Fundamental colors red, green, and violet-blue. See Primary colors, under Color.
n.	1.	A leading or primary principle, rule, law, or article, which serves as the groundwork of a system; essential part, as, the fundamentals of the Christian faith.

Noun	1.	fundamental - the lowest tone of a harmonic series Synonyms: first harmonic, fundamental frequency
Adj.	1.	fundamental - serving as an essential component; "a cardinal rule"; "the central cause of the problem"; "an example that was fundamental to the argument"; "computers are fundamental to modern industrial structure" Synonyms: cardinal, central, key, primal
	2.	fundamental - being or involving basic facts or principles; "the fundamental laws of the universe"; "a fundamental incompatibility between them"; "these rudimentary truths"; "underlying principles" Synonyms: rudimentary, underlying
	3.	fundamental - far-reaching and thoroughgoing in effect especially on the nature of something; "the fundamental revolution in human values that has occurred"; "the book underwent fundamental changes"; "committed the fundamental error of confusing spending with extravagance"; "profound social changes" Synonyms: profound

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