vestry

noun

Etymology: From Anglo-Norman vesterie, from Old French vestiaire (“room for vestments, dressing room”), from Latin vestiarium (“wardrobe”). Doublet of vestiary.

1. A room in a church where the clergy put on their vestments and where these are stored; also used for meetings and classes.

   “The choirboys change into their cassocks in the vestry.”

   “What a day, eh? Demmy, it's like the commencement of the rainy season in Bengal. But you'll find my carriage is watertight. Come along, my mother and Emmy are in the vestry.”

2. An assembly of persons (ad hoc or recurrent) who manage parochial affairs; so called because usually held in a vestry.
3. A committee of parishioners elected to administer the temporal affairs of a parish.

   “Near-synonyms: parochial church council, PCC, parish council (ecclesiastical sense, uncommon)”

   “The vestry meets on the first Tuesday of every month.”