clere·sto·ry also clear·sto·ry (klîrstôr′ē)
n. pl. clere·sto·ries
1. The upper part of the nave, transepts, and choir of a church, containing windows that rise above the roofs of the aisles.
2. A similar structure admitting light into an ancient building such as an Egyptian temple or a Roman basilica.
3. An upper portion of a wall containing windows, especially when rising above a lower roof.
[Middle English clerestorie : perhaps cler, giving light, clear; see CLEAR + storie, tier; see STORY2.]
(click for a larger image)clerestory
nave wall of a Gothic cathedral
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