The identification of others with oneself; specifically (in later use) = alter-egoism .
alter-egotism/ˌaltə(r)ˈɛɡətɪz(ə)m/ /ˌɔːltə(r)ˈɛɡətɪz(ə)m/ /ˌɒltə(r)ˈɛɡətɪz(ə)m/
Mid 19th century; earliest use found in Frederick Olmsted (1822–1903). From alter ego + -ism, with insertion of t after egotism.
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