Ecumenism

Ecumenism (or Oecumenism) is the idea that the different Christian denominations should work together more than they currently do. This idea is different from religious toleration. Over the years, Christianity has been split into many different movements. These separations are based on doctrine, on history, and what people do in everyday life. 
The term ecumenical comes from the Latin "oecumenicus", a phrase referring to "the whole world", meaning literally "inhabited" (lived in). In Christianity the qualification ecumenical is originally (and still) used in terms such as Ecumenical council and Ecumenical patriarch. The meaning pertains to the totality of the larger Church (such as the Catholic Church or the Orthodox Church). It is not restricted to one of its local churches or dioceses.