IPA: /ɑːrˈtʃaɪəˌsiːs/
KK: /ɑrʧˈdaɪəsɪs/
A large district under the care of a bishop in the Christian church, which includes several smaller dioceses.
The archdiocese held a special ceremony to celebrate its anniversary.
Archdiocese → It is formed from "arch-" (from Greek "archi-", meaning chief or principal) and "diocese" (from Greek "dioikesis", meaning administration or management). The term refers to a principal diocese, which is the chief administrative district of a church.
Think of 'arch-' meaning chief or principal, which helps you remember that an archdiocese is the main administrative area of a church.
No commonly confused words.