ecumenics

[ ek-yoo-men-iks or, esp. British, ee-kyoo- ]
/ ˌɛk yʊˈmɛn ɪks or, esp. British, ˌi kyʊ- /

noun (used with a singular verb)

the study of the Christian church in its aspect as a worldwide Christian community.

Origin of ecumenics

First recorded in 1935–40; see origin at ecumenical, -ics
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019