Certainly meaning
Undoubtedly; definitely.
This is certainly not my writing.
adverb
The definition of certainly is absolutely or definitely.
An example of certainly used as an adverb is in the sentence, "We will certainly buy some cookies," which means "We will absolutely buy some cookies."
adverb
Surely.
They certainly are hard workers.
adverb
By all means; of course.
You may certainly join us.
adverb
An emphatic affirmative answer; of course.
Would you like it with ice? Certainly, and with lemon please.
adverb
Beyond a doubt; surely.
adverb
Yes.
adverb
Origin of certainly
- certain + -ly
From Wiktionary