GoldenDict is described as 'Open-source dictionary program for PC computers that gives translations of words and phrases for different languages. It allows use of several popular dictionary file formats simultaneously' and is a very popular Dictionary in the education & reference category. There are more than 50 alternatives to GoldenDict for a variety of platforms, including Android, Web-based, Windows, Linux and iPhone apps. The best GoldenDict alternative is Wiktionary, which is both free and Open Source. Other great apps like GoldenDict are GoldenDict-ng, FreeDictionaryApp, WordReference and Lingoes.
Google Dictionary is a Chrome extension, whereas GoldenDict is a standalone program. You can't use the former without Chrome.