certainly

adverb

cer·​tain·​ly ˈsər-tᵊn-lē How to pronounce certainly (audio)
Synonyms of certainly
1
: in a manner that is certain : with certainty
2
: it is certain that : assuredly

Examples of certainly in a Sentence

It will certainly rain tomorrow. This year's festival was certainly much better than last year's. I'm certainly going to try. The new version is most certainly easier to use. The snake that bit her was almost certainly poisonous.
Recent Examples on the Web
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While a full overhaul of the entire system might not be practical, there is certainly no excuse for lawmakers to make things worse. Adam Hoffer, Chicago Tribune, 5 July 2026 Jackson certainly knows the challenges of eating well while working on patrol, with sometimes just a few minutes for a meal and only fast-food options available. Teri Figueroa, San Diego Union-Tribune, 5 July 2026 But the servers and butlers certainly step up and can be seen indulging young guests, giving parents the chance to dine uninterrupted. Condé Nast, Condé Nast Traveler, 5 July 2026 As a result, jet fuel dynamics can offer some clues into diesel (certainly a big cost for Club names FedEx Freight and FedEx Corp ). Zev Fima,kevin Stankiewicz, CNBC, 5 July 2026 See All Example Sentences for certainly

Word History

First Known Use

14th century, in the meaning defined at sense 1

Time Traveler
The first known use of certainly was in the 14th century

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Cite this Entry

“Certainly.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/certainly. Accessed 6 Jul. 2026.

Kids Definition

certainly

adverb
cer·​tain·​ly ˈsərt-ᵊn-lē How to pronounce certainly (audio)
1
: in a manner that is certain : for certain
the only event of which anything is certainly known
2
: without doubt : surely
certainly you can do it

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