This word is a combination of "gnosis" (knowledge) and "narcissism" (self-centeredness). So, gnosonarcissism is a self-centered view that one's level of knowledge is correct and/or complete despite what others know. This implies a lack of understanding that others might know more in areas of knowledge in either a horizontal way (breadth of knowledge) or a vertical way (depth of knowledge).

Because of his gnosonarcissism, he was unable to believe that the ideas of others could ever be better than his own ideas.
by Gregory V. Richardson July 9, 2006
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