uniformitarian

noun

uni·​for·​mi·​tar·​i·​an ˌyü-nə-ˌfȯr-mə-ˈter-ē-ən 

1

: an adherent of the doctrine of uniformitarianism

2

: an advocate of uniformity

uniformitarian adjective

Word History

First Known Use

1840, in the meaning defined at sense 1