fundamental

American  

[fuhn-duh-men-tl] / ˌfʌn dəˈmɛn tl /

adjective

1. serving as, or being an essential part of, a foundation or basis; basic; underlying.

   fundamental principles;

   the fundamental structure.

   Synonyms:

   primary, indispensable

2. of, relating to, or affecting the foundation or basis.

   a fundamental revision.

3. being an original or primary source.

   a fundamental idea.

4. Music. (of a chord) having its root as its lowest note.

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noun

1. a basic principle, rule, law, or the like, that serves as the groundwork of a system; essential part.

   to master the fundamentals of a trade.

2. Also called fundamental tone.  Also called fundamental note,.  Music.

   1. the root of a chord.

   2. the generator of a series of harmonics.

3. Physics. the component of lowest frequency in a composite wave.

fundamental British  

/ ˌfʌndəˈmɛntəl /

adjective

1. of, involving, or comprising a foundation; basic

2. of, involving, or comprising a source; primary

3. music denoting or relating to the principal or lowest note of a harmonic series

4. of or concerned with the component of lowest frequency in a complex vibration

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noun

1. a principle, law, etc, that serves as the basis of an idea or system

2. 1. the principal or lowest note of a harmonic series

   2. the bass note of a chord in root position

3. Also called: fundamental frequency.   first harmonic.  physics

   1. the component of lowest frequency in a complex vibration

   2. the frequency of this component

Other Word Forms

• fundamentality noun
• fundamentally adverb
• fundamentalness noun
• nonfundamental adjective
• nonfundamentally adverb
• unfundamental adjective
• unfundamentally adverb

Etymology

Origin of fundamental

First recorded in 1400–50; late Middle English, from Medieval Latin fundāmentālis “of, belonging to a foundation”; fundament, -al ¹

Explanation

When asked what the fundamental, or essential, principles of life are, a teenager might reply, "Breathe. Be a good friend. Eat chocolate. Get gas money." Fundamental has its roots in the Latin word fundamentum, which means "foundation." So if something is fundamental, it is a key point or underlying issue — the foundation, if you will — that the thing is built upon. Teachers argue that math fundamentals include memorizing the times tables and understanding long division. Many people would also argue that math fundamentals should include knowing how to use a calculator and knowing where the calculator's extra batteries are kept.

Example Sentences

But he continues to pitch because it constitutes a fundamental part of his identity.

From The Wall Street Journal • Apr. 10, 2026

“If we don’t recognize Rue or the others in some fundamental way, that’s risky,” Monk-Payton said.

From Los Angeles Times • Apr. 9, 2026

“Our recent results have not met our expectations, and we have taken immediate and fundamental actions to turnaround both our financial performance and our in-market performance.”

From Barron's • Apr. 9, 2026

Opponents of the reform argued that it would put a fundamental resource - water - at risk.

From BBC • Apr. 9, 2026

Of all the world’s errors, he seemed to feel, the most fundamental was the “erasing” of people, the “hiding away” of suffering.

From "Mountains Beyond Mountains" by Tracy Kidder and Michael French

Related Words

• central
• constitutional
• crucial
• elemental
• elementary
• essential
• indispensable
• integral
• intrinsic
• major
• necessary
• paramount
• principal
• radical
• significant
• structural
• theoretical
• underlying
• vital