foy·er / ˈfoiər; ˈfoiˌā/ • n. an entrance hall or other open area in a building used by the public, esp. a hotel or theater. ∎  an entrance hall in a house or apartment.ORIGIN: late 18th cent. (denoting the center of attention or activity): from French, ‘hearth, home,’ based on Latin focarius ‘kitchen servant,’ from focus ‘domestic hearth.’

foyer.
1. Lobby or entrance-hall of a theatre or other public building.

2. Area outside the auditorium for the audience to meet, promenade, mingle, talk, etc. It acts as a sound-barrier between the exterior and the auditorium.

3. Any public area in a large public or civic building between the exterior and the main parts of the building, i.e. an extended entrance-hall.

4. Room for gatherings or meetings.

5. Room for meetings, especially of actors and performers, in a theatre.

foyer XIX. — F. hearth, home :- Gallo-Rom. *focārium, f. L. focus fire (see FOCUS).