ecumenicism

[ ek-yoo-men-uh-siz-uh m or, esp. British, ee-kyoo- ]
/ ˌɛk yʊˈmɛn əˌsɪz əm or, esp. British, ˌi kyʊ- /

noun

ecumenicalism; ecumenism.

Origin of ecumenicism

First recorded in 1960–65; ecumenic(al) + -ism