English Reference
adjective · noun

fundamental

adj. · n.
US /ˌfəndəˈmɛnəɫ/ UK /fˌʌndəmˈɛntəl/ fun·da·men·tal

  1. 01 B2 Upper Intermediate Academic

    adj.forming the most important or basic part of something.

    adj.serving as a foundation or core basis; essential to the nature of a system or idea.

    Simple

    Freedom of speech is a fundamental right in many countries.

    In context

    The research team identified a fundamental flaw in the original hypothesis, necessitating a complete revision of the experimental framework.

    Usage

    Often used to describe rights, principles, or changes.

  2. 02 B2 Upper Intermediate Academic

    n.a basic rule, fact, or idea that other things are based on.

    n.a central principle or primary rule that serves as a building block for a complex system of thought.

    Simple

    The course covers the fundamentals of graphic design, starting with color theory.

    In context

    Before attempting advanced calculus, students must demonstrate a firm grasp of algebraic fundamentals.

    Usage

    Frequently used in the plural form 'fundamentals' when referring to education or skills.

  3. 03 C2 Proficiency Technical Music

    n.the lowest frequency of a sound or signal.

    n.the lowest frequency of a periodic waveform or the lowest partial of a complex musical tone.

    Simple

    The fundamental of the note was clear, even with the background noise.

    In context

    The timbre of the instrument is determined by the relationship between the fundamental and its various overtones.

    Usage

    In acoustics, it is often referred to as the 'fundamental frequency'.

    fundamental frequency
    overtoneharmonic

Usage fundamental human · fundamental research · fundamental aspect

Should Meta ultimately lose a case of this scale, it could force fundamental changes to the way young people experience social media.

BBC News· 16 Aug 2026

In those conditions, the most fundamental chemical reactions in the universe take place.

Phys.org· 16 Aug 2026

From Late Latin fundamentālis, from Latin fundamentum (“foundation”), from fundō (“to lay the foundation (of something), to found”), from fundus (“bottom”), from Proto-Indo-European *bʰudʰmḗn.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Origin ine-pro *bʰudʰmḗn
Level B2 · Upper Intermediate
Frequency Common
Updated