Definition of certain
- the house has a certain charm
- it is certain that we exist
- the certain advance of age
- she is certain to do well
- I am certain they are right
I'm fairly certain that I'll be on time.
a certain person told me that today is your birthday
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'certain.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
First Known Use: 13th centurySee Words from the same year
: not having any doubt about something : convinced or sure
—used with it to say that something is known to be true or correct
—used to refer to something or someone that is not named specifically
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