The Collaborative International Dictionary of English v.0.48:

Entr'ee \En`tr['e]e"\, n. [F. See Entry.]
   1. A coming in, or entrance; hence, freedom of access;
      permission or right to enter; as, to have the entr['e]e of
      a house.
      [1913 Webster]

   2. (Cookery) In French usage, a dish served at the beginning
      of dinner to give zest to the appetite; in English usage,
      a side dish, served with a joint, or between the courses,
      as a cutlet, scalloped oysters, etc. [obsolescent]
      [1913 Webster]

   3. the dish which comprises the main course of a meal,
      especially in a restaurant; as, there were many entrees on
      the menu.
      [PJC]

WordNet (r) 3.0 (2006):

entree
    n 1: the principal dish of a meal [syn: entree, main course]
    2: the right to enter [syn: entree, access, accession,
       admission, admittance]
    3: something that provides access (to get in or get out); "they
       waited at the entrance to the garden"; "beggars waited just
       outside the entryway to the cathedral" [syn: entrance,
       entranceway, entryway, entry, entree]
    4: the act of entering; "she made a graceful entree into the
       ballroom"