Force Snow Leopard's Dictionary.app to reuse definition window

The Dictionary.app in Snow Leopard has been driving me nuts. If you use LaunchBar or Spotlight (or probably any other method of sending a word to Dictionary.app), it opens a new window. And then another. And then another. This might be handy if the window bar was updated to show the word that you had looked up, but it doesn't, meaning that the extra windows are just clutter.

Before 10.6, Dictionary.app reused the same window for each new definition. If you wanted to go back to a previous word, you could simply use the "Back" button. As we've heard countless times, Snow Leopard has been about subtle refinements, but this was a step backwards to me. I was surprised that there isn't a Preference setting to reuse the same window or open a new one.

In a fit of frustration yesterday, I posted a bounty on Twitter and asked Rob Griffiths to see if he knew of an answer. Rob is the proprietor of MacOSXHints.com which I consider essential reading for Mac users (I have even submitted a few tips of my own over the years). I knew if anyone could find an answer, it was Rob.

Well, it turns out they don't call him Rob "The Hints Guru" Griffiths for nothing. Not long after my cry for help, Rob figured out how to Force Dictionary to show definitions in one window. As you might expect, it involves entering a command in Terminal.app while Dictionary.app is not running:

Voilà! Dictionary will now revert back to the 10.5 and earlier behavior of using one window for all definitions.

Rob must truly be credited for discovering this gem, because (as of this writing) Google comes up 100% empty when looking for 'ProhibitNewWindowForRequest'. When was the last time you tried to Google something and came up completely empty? That doesn't happen often anymore!

Turns out that Rob used another tip from his site to find hidden preferences (something else which has gotten more difficult in Snow Leopard). It's the circle of life... or at least, tips.

Thanks again, Rob. Now where do you want me to send your Ferrari? (You'll have to read Rob's post to get that joke. It also explains how to undo this change if you decide you want to revert to the standard 10.6 behavior.)