Below are some screenshots of Fora Reader in action. Though they are taken on a Windows computer, Mac OS X and Linux functionality is identical except respective look and feels.

Hover activation requires no clicks at all.

Focused tool window provides functionality for better browsing
results

Cross-lookup couples all your dictionaries together

Split panels provide integrated dictionary view

Dictionary manager gives you complete control over your dictionaries

Background mode continuously monitors clipboard and captures words to
translate
Fora Reader v2