You won't find any program, and that includes GoldenDict, which can read *.BDC files (except for Babylon itself). *.BDC are just compiled version of the original *.BGL files. You have to find the BGL file in the Babylon's cache folder and use that in GoldenDict. This question was asked many times in this forum. Please use Google to search for the answer:
https://www.google.com/#q=site:goldendi ... afe=activeRegards,
Chulai