adjective
    
    not used before a noun [more ~; most ~] :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 say that something will definitely happen or that someone will definitely do something
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    always used before a noun - used to refer to something or someone that is not named specifically
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    a certain
    
    used to refer to a quality that is noticed but that is difficult to explain or describe
    
    
    
    
    
    formal - used with the name of a person you do not know
    
    
    
    for certain
    
    without a doubt :definitely or certainly
    
    
    
    
    
    make certain
    
    to do something or find out something so that you have no doubt about whether something is true, correct, will happen, etc.
    
    
    
    
    
    
    
    
    
    pronoun
    
    formal :certain ones :particular members of a group :some
    
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