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Synonyms

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
"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

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

"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 certainly

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

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.

“These rules of thumb can certainly give Americans a ballpark estimate for their own wealth-management goals,” said Roberts.

From MarketWatch

"Execution is another thing and I certainly didn't execute as well as I could have."

From BBC

It has shown it has some influence in the Middle East, and it certainly has ambitions to gain more leverage in the future.

From BBC

In the lavish memorial erected by his grieving widow, Queen Victoria, Prince Albert is golden, but few world leaders are permanently gilded, and certainly not before their deaths.

From Los Angeles Times

“It would certainly catch me by surprise and feel a little reckless. And I think I’d probably be the last person people would be worried about,” Cooke said.

From Los Angeles Times

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.