Dictionary.com
Thesaurus.com
Synonyms

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.


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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

noun

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

    1. the principal or lowest note of a harmonic series

    2. the bass note of a chord in root position

  2. Also called: fundamental frequency.   first harmonicphysics

    1. the component of lowest frequency in a complex vibration

    2. the frequency of this component

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

They know that fundamental questions must be answered before we rush forward.

From The Wall Street Journal • Apr. 2, 2026

Additionally, Goldman Sachs predicts that central bank demand will remain a fundamental pillar of support, averaging about 60 metric tons monthly, once price volatility dissipates.

From MarketWatch • Apr. 2, 2026

But unless it resolves the deeper contradictions — unless it explains not just what is happening, but why it had to happen and how it will end — it will not change the fundamental dynamic.

From Salon • Apr. 1, 2026

“What we’re seeing in the market today is much more about supply recovery and timing shifts than any fundamental change in consumption,” said CEO Sherman Miller on the earnings call.

From Barron's • Apr. 1, 2026

Quintilian is a fundamental reference point for Arnauld: ‘Quintilian and all the other rhetoricians, Aristotle and all the philosophers...’

From "The Invention of Science" by David Wootton