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

Etymology

Origin of fundamental

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

See Examples For:

fundamental

But they are benefiting from higher interest rates and continue to return cash to investors through share buybacks and dividends, says Blackrock’s chief investment officer for fundamental equities, Helen Jewell.

From The Wall Street Journal ● Aug. 21, 2026

“You read a lot about AI and there are a lot of companies that their fundamental existence is being questioned because of AI and what it can do,” Williams said.

From Los Angeles Times ● Aug. 21, 2026

But experts said some aspects of the bureau’s release raise fundamental questions.

From Salon ● Aug. 21, 2026

"These young people would have been in Years 6, 7 and 8, and so possibly haven't necessarily got the basic foundations in these subjects which are really fundamental."

From BBC ● Aug. 20, 2026

It would take two centuries to figure out that it's the living stuff inside cells that makes them the fundamental unit of life.

From "Phineas Gage" by John Fleischman

Related Words

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