English Reference
noun

diocese

n.
US /ˈdaɪəˌsiz/ UK /dɪəʊsˈiːz/ dio·cese UK spelling dioceses

  1. 01 C1 Advanced Formal Religion

    the area or group of churches that a bishop is in charge of.

    a territorial unit of church administration under the spiritual and jurisdictional care of a bishop.

    Simple

    The local diocese organized a food drive to help families in the city.

    In context

    The archbishop visited every parish within the diocese to discuss the new educational initiatives and community outreach programmes.

    Usage

    Often used with the definite article 'the' when referring to a specific local district.

    bishopricsee
  2. 02 C2 Proficiency ArchaicTechnical

    a large district used for governing the Roman Empire in ancient times.

    a major administrative division of the later Roman Empire, typically consisting of several provinces.

    Simple

    In ancient Rome, a diocese was a large area managed by a high official.

    In context

    Under the reforms of Diocletian, the empire was partitioned into several dioceses to streamline tax collection and military administration.

    Teacher's tip

    This sense is strictly historical; in modern English, the word almost exclusively refers to church geography.

The diocese of the nearby municipality of Atlacomulco said two priests were injured but are expected to survive.

Al Jazeera· 6 Sept 2026

From Middle English diocise, from Old French diocese, from Late Latin diocēsis, from Latin dioecēsis (“district under a governor”), from Ancient Greek διοίκησις (dioíkēsis, “internal administration”).

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Origin Ancient Greek διοίκησις
Level C1 · Advanced
Frequency Frequent
Updated