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certainly

[sur-tn-lee]
See more synonyms for certainly on Thesaurus.com
adverb
  1. with certainty; without doubt; assuredly: I'll certainly be there.
  2. yes, of course: Certainly, take the keys.
  3. surely; to be sure: He certainly is successful.
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Origin of certainly

Middle English word dating back to 1250–1300; see origin at certain, -ly
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for certainly

Contemporary Examples

Historical Examples

  • She certainly knew he was liable to go at any time, in exactly the way he did go.

    The Spenders

    Harry Leon Wilson

  • I certainly did need you to come along right now and set me straight.

    The Spenders

    Harry Leon Wilson

  • "Certainly, Robert," was the reply, but the lawyer's manner showed some surprise.

    Brave and Bold

    Horatio Alger

  • Too bad, though—you certainly need a wife to take the conceit out of you.

    The Spenders

    Harry Leon Wilson

  • "You certainly do know your business, son," said Uncle Peter, fervently.

    The Spenders

    Harry Leon Wilson


British Dictionary definitions for certainly

certainly

adverb
  1. with certainty; without doubthe certainly rides very well
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sentence substitute
  1. by all means; definitely: used in answer to questions
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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

Word Origin and History for certainly

adv.

c.1300, in all main modern senses, from certain + -ly (2).

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Online Etymology Dictionary, © 2010 Douglas Harper