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Synonyms

undoubtedly

American  
[uhn-dou-tid-lee] / ʌnˈdaʊ tɪd li /

adverb

  1. certainly or definitely; without doubt.

    Seats will undoubtedly sell out fast for this one-night performance.


undoubtedly British  
/ ʌnˈdaʊtɪdlɪ /

adverb

  1. certainly or definitely; unquestionably

    he is undoubtedly talented

  2. (sentence modifier) without doubt; certainly or indisputably

    undoubtedly there will be changes

"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

Etymology

Origin of undoubtedly

First recorded in 1500–50; undoubted ( def. ) + -ly ( def. )

Explanation

Undoubtedly means certainly. If you are undoubtedly beautiful, then everyone agrees you are attractive. No one could think otherwise. There are a lot of things in life that people doubt. However, when you're sure of something or feel strongly about it, this is a handy word. A beautiful spring day is undoubtedly wonderful. Dogs undoubtedly love to chase squirrels. Adults undoubtedly love to drink coffee in the morning, and kids undoubtedly love to get a day off from school. You are undoubtedly aware that this is a long explanation for something as simple as this word.

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Vocabulary lists containing undoubtedly

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.

If so, the Lakers undoubtedly would be interested.

From Los Angeles Times • Apr. 13, 2026

If AR's parents had reported this information before the 2024 attack, AR would undoubtedly have been arrested and he would either have been taken into care or held in custody, the report explained.

From BBC • Apr. 13, 2026

Reilly added that while price action in the sector is undoubtedly negative, it should be viewed through the lens of higher Treasury bond yields, which have compressed valuations even as earnings expectations have improved.

From Barron's • Mar. 31, 2026

A city on the moon would undoubtedly be an incredible accomplishment.

From MarketWatch • Mar. 31, 2026

ALBUS: Listen, I’ve got quite a lot of packing to do, and you undoubtedly have Ministry work coming out of your ears, so .

From "Harry Potter and the Cursed Child" by J.K. Rowling