Word Study
retrochoir
CIDE DICTIONARY
retrochoir, n. [Pref. retro- + choir.].
Any extension of a church behind the high altar, as a chapel; also, in an apsidal church, all the space beyond the line of the back or eastern face of the altar. [1913 Webster]
OXFORD DICTIONARY
retrochoir, n. the part of a cathedral or large church behind the high altar.
Etymology
med.L retrochorus (as RETRO-, CHOIR)
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