Know-it-all

A know-it-all or know-all is a person who constantly presents their input as though they were professionally trained, schooled or have firsthand insight into subjects when it is evident this is not the case. A know-it-all will quickly reject opinions, suggestions, thoughts and commentary from others as incorrect, nonsensical and disruptive.

The German word Besserwisser is also used in some languages, literally meaning "better knower".

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