clerestory

• clearstory, clerstory

From Middle English clerestory, from clere (“clear: light, lighted”) + story (“storey/story: level of a building”).

• (General American, Canada) enPR: klîr'-stôr-ē, IPA^(key): /ˈklɪəɹ.stɔːɹi/
• Hyphenation: clere‧stor‧y

clerestory (plural clerestories)

1. (architecture) The upper part of a wall containing windows to let in natural light to a building, especially in the nave, transept and choir of a church or cathedral.
   • 1939 July, “Overseas Railways: Baltic Island Railways”, in Railway Magazine, page 49:

     On the Visby-Västerhejde Railway there is a steam car. [...] The upperworks consist of a short clerestory coach body with end platforms and the engine chimney protruding from the roof like a stovepipe.

   • 1951 January, “The Inner Circle and its Rolling Stock”, in Railway Magazine, page 59:

     The cars built before 1913 had clerestory roofs, after the American style, and also were provided with gates and end vestibule platforms requiring gatemen.

• triforium