What is (a) The projection of any part of a building in a rounded form. (b) Any out-of-door seat in stone, large enough for several persons; esp., one of curved form called?

exedra — (Arch.) (a) The projection of any part of a building in a rounded form. (b) Any out-of-door seat in stone, large enough for several persons; esp., one of curved form. (Webster's 1913.)

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