The Collaborative International Dictionary of English v.0.48:
Parousia \Pa*rou"si*a\, n. [NL., fr. Gr. ?. See Parusia.] (a) The nativity of our Lord. (b) The last day. --Shipley. [1913 Webster]WordNet (r) 3.0 (2006):
Parousia n 1: (Christian theology) the reappearance of Jesus as judge for the Last Judgment [syn: Second Coming, Second Coming of Christ, Second Advent, Advent, Parousia]