Definition of retrochoir in English:

retrochoir

Pronunciation /ˈretrōˌkwī(ə)r/ /ˈrɛtroʊˌkwaɪ(ə)r/

noun

  • The interior of a cathedral or large church behind the high altar.

    ‘Some of the larger Cathedrals have a retrochoir to the east of the high altar and separated from the sanctuary by a screen or reredos.’
    • ‘The shrine (i.e., box of Swithun's remains) was high on a wall, behind the altar screen, and the barn-like retrochoir behind was built to accommodate the pilgrims who crawled through a small hole beneath the shrine.’

Origin

Mid 19th century from medieval Latin retrochorus(see retro-, choir).