fideism
noun
fi·de·ism ˈfē-(ˌ)dā-ˌi-zəm 
: reliance on faith rather than reason in pursuit of religious truth
fideist
ˈfē-ˌdā-ist
noun fideistic
ˌfē-(ˌ)dā-ˈi-stik
adjective 
Word History
Etymology
borrowed from French fidéisme, from Latin fidēs "trust, belief, faith" + French -isme -ism — more at faith entry 1
First Known Use
1885, in the meaning defined above