Word Study
superaltar
CIDE DICTIONARY
superaltar, n.
A raised shelf or stand on the back of an altar, on which different objects can be placed; a predella or gradino. [1913 Webster]
OXFORD DICTIONARY
superaltar, n. Eccl. a portable slab of stone consecrated for use on an unconsecrated altar etc.
Etymology
ME f. med.L superaltare (as SUPER-, ALTAR)
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