Simple Definition of certainly
: without doubt
: of course
Examples of certainly
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.
First Known Use of certainly
CERTAINLY Defined for Kids
Definition of certainly
1 : without fail <I will certainly help.>
2 : without doubt <You certainly don't look your age.>
Seen and Heard
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