Relating to or characteristic of egocentricity; marked by excessive self-centeredness.
From egocentric with the suffix -istic (from Greek -istikos), which intensifies and emphasizes the quality being described.
You'll rarely see this word because 'egocentric' or 'egotistical' works fine, making 'egocentristic' one of those redundant synonyms that English creates by accident but nobody actually uses.
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