If you use Spotlight to look up Dictionary definitions, you may find it annoying that they show up near the bottom of the list. While you can change the order of most Spotlight categories from the Search Results tab of the Spotlight pane in System Preferences, Dictionary isn't in that list.
However, there is a hack, involving some simple editing of the ~/Library/Preferences/com.apple.spotlight.plist file. A recent post on Stack Exchange explains what to do. You open the file with Xcode, then add a Dictionary item, which will allow you to move the Dictionary category to where you want in the Spotlight results. See the post linked above for full details, or see this blog post in Chinese explaining the procedure.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20130203231204779