certainly

American  

[sur-tn-lee] / ˈsɜr tn li /

adverb

1. with certainty; without doubt; assuredly.

   I'll certainly be there.

2. yes, of course.

   Certainly, take the keys.

3. to be sure; surely.

   He certainly is successful.

---

certainly British  

/ ˈsɜːtənlɪ /

adverb

1. with certainty; without doubt

   he certainly rides very well

---

1. by all means; definitely: used in answer to questions

Etymology

Origin of certainly

First recorded in 1250–1300; Middle English; certain + -ly

Example Sentences

But assuming that some reading this will want to know how it follows, differs from or compares to the original — which was certainly the first thing on my mind — let us count the ways.

From Los Angeles Times

In Washington, that is certainly the fear of the Democratic vice-chairman of the Senate Intelligence Committee, Senator Mark Warner.

From BBC

Say what you want about Musk, but he certainly kept it interesting in 2025.

From The Wall Street Journal

His hunger for success has not diminished and winning is certainly not getting old for the teenager.

From BBC

“We probably have an OK market, but certainly not what we’ve seen in the last couple years,” said Mark Hackett, chief market strategist at Nationwide.

From The Wall Street Journal

Related Words

• absolutely
• assuredly
• exactly
• surely