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Webster 1913 Edition
Mezzanine
Mez′za-nine
,Noun.
1.
(Arch.)
(a)
Same as
Entresol
. (b)
A partial story which is not on the same level with the story of the main part of the edifice, as of a back building, where the floors are on a level with landings of the staircase of the main house.