The Narthex reference article from the English Wikipedia on 24-Apr-2004
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Narthex

The Narthex is the entrance or lobby area of a church.

In old cathedrals this area was usually separated from the nave of the church by a railing or screen. In modern churches the narthex often separates the worship area by a wall with doors opening into the nave. Today lobby is the clearer meaning as well as easiest to pronounce.