Handy dandy pop-up dictionary

In any app that uses Cocoa text widgets (Safari, for example), you can hover the mouse cursor over a word and press cmd-ctrl-d to get a tool-tip like bubble that shows the word’s definition and a button to open Dictionary.app to that word. Try it on an archaic word the comprehension of which eludes you before I get overly loquacious.

[From Finer Things in Mac, Handy dandy pop-up dictionary]

This is much better than the 金山詞霸 that my colleagues are using. "You" get to decide if you want to look up the meaning of a word, instead of letting a background process hog your CPU on every mouse-over English word, bravo!