superegoist

noun

su·​per·​ego·​ist ˌsü-pər-ˈē-gə-wist 

-gō-ist

plural superegoists

: an extreme egoist : one who is excessively self-centered or devoted to self-interest

Lincoln had made the mistake of being humble with a superegoist. The egoist mistook humility for weakness.

—T. Harry Williams

Word History

First Known Use

1909, in the meaning defined above