What is "opisthodome"

Opisthodome \O*pis"tho*dome\, n. [L. opisthodomus, Gr. ?; 'o`pisqen behind + do`mos house: cf. F. opisthodome.] (Arch.) A back chamber; especially, that part of the naos, or cella, farthest from the main entrance, sometimes having an entrance of its own, and often used as a treasury.

n. (context architecture English) A back chamber; especially, that part of the naos, or cella, farthest from the main entrance, sometimes having an entrance of its own, and often used as a treasury.