‌Are you looking for an English - Turkish dictionary? Here is, TurkDict the first Turkish dictionary on the Mac App Store comes with great features :

• English to Turkish and Turkish to English dictionaries with over 200,000 definitions.
• Offline pronunciation for both Turkish and English languages.
• American and British accent voice
• Bookmark and search history.
• Automatic word suggestion.
• Quick search using Services menu.
• Support quick search with PopClip extension.