Webster's Revised Unabridged Dictionary · 1913

Antechamber

Antechamber ({not transcribed}) , noun

[Compare French antichambre.]

1.
A chamber or apartment before the chief apartment and leading into it, in which persons wait for audience; an outer chamber. See Lobby.
2.
A space viewed as the outer chamber or the entrance to an interior part.
The mouth, the antechamber to the digestive canal. — Todd & Bowman