latarnia = roof lantern

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Note added at 53 mins (2013-12-20 23:18:24 GMT)
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Latarnia – cylinder umieszczony na górnym pierścieniu kopuły z otworami doświetlającymi pomieszczenie przekryte kopułą. Latarnia zazwyczaj przykrywana była hełmem. Rozwiązanie często stosowane w renesansie i baroku. W Polsce ze znanych kopuł z latarnią należy wymienić przykrycie Kaplicy Zygmuntowskiej na Wawelu.
Latarnią nazywana jest także nadbudówka z oknami nad dachem doświetlająca pomieszczenie pod nim (np. klatkę schodową).
http://pl.wikipedia.org/wiki/Latarnia_(architektura)

English equivalent: Roof lantern
A roof lantern is a daylighting cupola architectural element. Architectural lanterns are atop a larger roof and provide natural light into the space or room below. In contemporary use it is an architectural skylight structure. The term 'roof top lantern' is used to describe the lighted decorative lanterns atop taxi cabs in Japan, designed to reflect the cultural heritage of Japanese paper lanterns.

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Note added at 53 mins (2013-12-20 23:18:34 GMT)
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http://en.wikipedia.org/wiki/Roof_lantern


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Note added at 58 mins (2013-12-20 23:23:11 GMT)
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OR: DOUBLE roof lantern dome/cupola

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Note added at 1 hr (2013-12-20 23:27:58 GMT)
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Roof lantern Home Design Photos
http://www.houzz.com/roof-lantern

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Note added at 1 hr (2013-12-20 23:28:48 GMT)
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A roof lantern window, also called a "cupola" window is an appropriate window addition to both older and newer building projects. Roof lantern replacement windows are installed in flat roofs and add light and a transformative look to the room below. Roof lantern windows may cover the entire roof area or can be installed in one section of the roof. The roof replacement window may be comprised of any number of glazing panels which offer a range of design options. This variety makes the roof lantern window a suitable choice for any home remodeling project.
http://www.zissil.com/topics/Roof-Lantern-Cupola-Windows

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Note added at 16 hrs (2013-12-21 14:49:48 GMT)
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One should be able to simplify this expression as follows:
TWO-LANTERN DOME
TWO-LANTERNED DOME
I think the "roof" is understood, since this is at domed structure.

Lantern refers to the windows through which sunlight can go in or inside lighting can shine out.