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adverb cer·tain·ly \-lē\

Simple Definition of certainly

  • : without doubt

  • : of course

Source: Merriam-Webster's Learner's Dictionary

Full Definition of certainly

  1. 1 :  in a manner that is certain :  with certainty

  2. 2 :  it is certain that :  assuredly

Examples of certainly in a sentence

  1. It will certainly rain tomorrow.

  2. This year's festival was certainly much better than last year's.

  3. I'm certainly going to try.

  4. The new version is most certainly easier to use.

  5. The snake that bit her was almost certainly poisonous.

14th Century

First Known Use of certainly

14th century

CERTAINLY Defined for Kids


adverb cer·tain·ly \ˈsər-tən-lē\

Definition of certainly for Students

  1. 1 :  without fail <I will certainly help.>

  2. 2 :  without doubt <You certainly don't look your age.>

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