The Collaborative International Dictionary of English v.0.48:

Hacienda \Ha`ci*en"da\ ([aum]`th[-e]*[asl]n"d[.a] or
   h[aum]`s[i^]*[e^]n"d[.a]), n. [Sp., fr. OSp. facienda
   employment, estate, fr. L. facienda, pl. of faciendum what is
   to be done, fr. facere to do. See Fact.]
   1. A large estate where work of any kind is done, as
      agriculture, manufacturing, mining, or raising of animals;
      a cultivated farm, with a good house, in distinction from
      a farming establishment with rude huts for herdsmen, etc.;
      -- a word used in Spanish-American regions.
      [1913 Webster]

   2. The main residence of a hacienda[1].
      [PJC]

WordNet (r) 3.0 (2006):

hacienda
    n 1: a large estate in Spanish-speaking countries
    2: the main house on a ranch or large estate

Moby Thesaurus II by Grady Ward, 1.0:

55 Moby Thesaurus words for "hacienda":
   arable land, barnyard, barton, cattle ranch, chicken farm,
   collective farm, cotton plantation, croft, dairy farm, demesne,
   demesne farm, dry farm, dude ranch, estate, factory farm, fallow,
   farm, farmery, farmhold, farmland, farmplace, farmstead, farmyard,
   fruit farm, fur farm, grain farm, grange, grassland, home place,
   homecroft, homefarm, homestead, house and grounds, house and lot,
   kibbutz, kolkhoz, location, mains, manor farm, messuage, orchard,
   pasture, pen, place, plantation, poultry farm, ranch, rancheria,
   rancho, sheep farm, station, steading, stock farm, toft,
   truck farm