The Collaborative International Dictionary of English v.0.48:

dacha \dacha\ n. [Russian.]
   a Russian country house, especially a cottage used in the
   summer.
   [WordNet 1.5 +PJC]

WordNet (r) 3.0 (2006):

dacha
    n 1: Russian country house

Moby Thesaurus II by Grady Ward, 1.0:

38 Moby Thesaurus words for "dacha":
   Dymaxion house, White House, adobe house, building, casa,
   cliff dwelling, consulate, country house, country seat, deanery,
   dwelling house, edifice, embassy, erection, fabric, farm,
   farmhouse, hall, house, houseboat, lake dwelling, living machine,
   lodge, manor house, manse, parsonage, penthouse,
   prefabricated house, presidential palace, ranch house, rectory,
   roof, skyscraper, sod house, split-level, structure, town house,
   vicarage