Characterized by egoism; excessively self-centered and self-interested; relating to egoistic philosophy or behavior.
From egoistic with the additional suffix -al, creating an extended adjective form. This is somewhat redundant with egoistic but both forms coexist in English.
English let two versions of the same word coexist—'egoistic' and 'egoistical'—which happens more often than you'd think, creating endless confusion in spelling and making grammar teachers tired.
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