A container made to house and honor a relic of Christ, a saint, or a holy place, frequently among the most elaborate objects of Catholic sacred art.
A reliquary is a container made to house and honor a relic. Reliquaries may take the form of caskets, crosses, architectural shrines, busts, arms, heads, feet, pendants, or elaborate metalwork constructions enriched with gems and enamel.
Etymology
From Latin reliquiae, “remains” or “relics.”
Sculptor Notes
The form of a reliquary often signals the relic within. A sculpted arm reliquary, for example, turns the container itself into an image. This union of object, image, precious material, and sacred content is one of the clearest examples of function shaping Catholic sculpture.
References
https://www.metmuseum.org/art/collection/search/193674