Smart Dictionary (by ketnoitienganh.com)

With this extension you can:
- lookup word definitions in any web site you visit
- select word to lookup definitions conveniently by double click on the word
- login to ketnoitienganh.com then any word you looked up is saved to your account. You can create group of looked up word and exercise with it.
- many exercise tool on ketnoitienganh.com help you exercise and remember words very fast.