feretory
A receptacle that houses relics of saints.
His remains were placed inside a new and rich feretory, on a platform behind the high altar.
An area of a church where relics are kept.
Where it comes from
From Middle English feretory, fertre, feretre, et al., from Anglo-Norman fertre, from Latin feretrum (“bier, funeral litter”), from Ancient Greek φέρετρον (phéretron), from the verb φέρω (phérō, “to carry”). Doublet of feretrum.
Adapted from the Wiktionary entry feretory (CC BY-SA 4.0).