certainly

adverb

cer·​tain·​ly ˈsər-tᵊn-lē 

1

: in a manner that is certain : with certainty

2

: it is certain that : assuredly

Synonyms

• all right
• alright
• assuredly
• clearly
• definitely
• doubtless
• easily
• forsooth
• hands down
• inarguably
• incontestably
• incontrovertibly
• indeed
• indisputably
• plainly
• really
• so
• sure
• surely
• truly
• unarguably
• undeniably
• undoubtedly
• unquestionably

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

The film has been steadily playing in theaters for months and will certainly continue to be shown for a long time. —Nancy Tartaglione, Deadline, 10 Feb. 2025

His disses and phenomenal momentum certainly helped, but several factors converged. —Andre Gee, Rolling Stone, 10 Feb. 2025

Dishwasher-safe Dishwasher-safe glasses are the easiest to clean, which will certainly be welcome after spending a couple of hours enjoying a few drinks with friends. —Bestreviews, The Mercury News, 10 Feb. 2025

This certainly includes oats but can also be made of quinoa, freekeh, rice, barley, farro, buckwheat or any number of other grains. —Tammy Algood, The Tennessean, 10 Feb. 2025

Word History

First Known Use

14th century, in the meaning defined at sense 1

Phrases Containing certainly

• certainly not

Kids Definition

certainly

adverb

cer·​tain·​ly ˈsərt-ᵊn-lē 

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