Joined or combined; made one; made to agree; allied; harmonious: as, a united household.In Roman Catholic usage, noting those communities which have separated from Oriental churches and united with the Roman Catholic Church in what it holds to be essential, but preserve an individual and distinctive church organization, acknowledging the supremacy of the Pope, and accepting the doctrinal decisions of the Roman Catholic Church, while retaining to some extent their ancient liturgy, rites, discipline, and usages.