'Mezzanine' definitions:

Definition of 'mezzanine'

noun

First or lowest balcony [syn: mezzanine, first balcony]

noun

Intermediate floor just above the ground floor [syn: mezzanine, mezzanine floor, entresol]

From: GCIDE

Mezzanine \Mez"za*nine\, n. [F. mezzanine, It. mezzanino, fr. mezzano middle, fr. mezzo middle, half. See Mezzo.]
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. [1913 Webster]
2. A flooring laid over a floor to bring it up to some height or level. [Webster 1913 Suppl.]
3. Also
mezzanine floor. (Theat.) A floor under the stage, from which various contrivances, as traps, are worked. [Webster 1913 Suppl.]
4. The lowest balcony in a theater, or the forward part of the first balcony. [PJC]