anti-conventional

adjective

an·​ti-con·​ven·​tion·​al

ˌan-tē-kən-ˈven(t)-sh(ə-)nəl,

ˌan-tī- 

: opposed to conventional methods and attitudes : emphatically and deliberately unconventional

running an anti-conventional campaign

Word History

First Known Use

1826, in the meaning defined above