Dicty is an education and reference application designed to help users learn and master foreign languages. It consists of an interactive dictionary, phrasebook, and flashcards. The dictionary includes translations for words, phrases, and idioms in over 30 languages, and the phrasebook includes commonly used phrases in the target language. The flashcards allow users to practice their language-learning skills by presenting users with random words and phrases in the target language and allowing them to practice translating them into their native language. Dicty also includes a variety of helpful language-learning tips, tricks, and strategies. In addition, users can create their own custom dictionary and phrasebook entries, and sync their data across multiple devices.
GoldenDict
StarDict
MDict
Lexpanse
Dictionary Universal
Discontinued The project seems to be no longer updated. Last version, 3.0.6, released in January 2015, but can still be downloaded from SourceForge.