superconfident

adjective
su·​per·​con·​fi·​dent | \ ˌsü-pər-ˈkän-fə-dənt How to pronounce superconfident (audio) , -ˌdent\

Definition of superconfident

: extremely confident a superconfident performer wasn't superconfident about their chances

First Known Use of superconfident

1866, in the meaning defined above

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