fundamentally

American  

[fuhn-duh-men-tl-ee] / ˌfʌn dəˈmɛn tl i /

adverb

1. in a fundamental and essential way; centrally and foundationally.

   a nine-point plan that will fundamentally transform our system of eldercare.

2. as regards the basic nature, character, or truth of something; basically and often emphatically.

   Fundamentally, they just want their independence.

---

fundamentally British  

/ ˌfʌndəˈmɛntəlɪ /

adverb

1. in a way that affects the basis or essentials; utterly

   the terms of engagement have been fundamentally altered

2. (sentence modifier) in essence; at heart

   fundamentally, we want our lives to be safe

---

Other Word Forms

• nonfundamentally
  adverb
• unfundamentally
  adverb

Etymology

Origin of fundamentally

First recorded in 1600–20; fundamental ( def. ) + -ly ( def. )

Explanation

The word fundamentally isn’t fun, exactly, but it does describe things that are true through and through. Vegetarians and meat eaters often have fundamentally different ideas about what makes a healthy meal. Anything fundamental has to do with the foundation or bare bones of something. Similarly, anything described fundamentally is getting down to the essence. Lying is fundamentally dishonest. If something is fundamentally wrong, don’t do it! If you and your dad have fundamentally different opinions about restaurants, it’s better to make dinner at home. This word means about the same as basically or essentially. If something is fundamentally true, it's true in a deep sense.

Example Sentences

See Examples For:

fundamentally

It doesn’t feel as vulnerable, whereas acting, there’s something fundamentally so indulgent about it.”

From Los Angeles Times ● Aug. 10, 2026

The fact that Saturn's cusp is displaced toward dusk provides evidence that a planet's rotation rate can fundamentally reshape its nearby space environment.

From Science Daily ● Aug. 10, 2026

“All of our customers are operating in a fundamentally different environment than they were even a year ago,” he said.

From MarketWatch ● Aug. 6, 2026

Heller decision, which fundamentally changed the country’s understanding of the amendment.

From Slate ● Aug. 6, 2026

You have to agree in advance that man is fundamentally a bad lot, out for himself alone, displaying such graces as affection and compassion only as learned habits.

From "The Lives of a Cell" by Lewis Thomas