Spotlight in Leopard gained quite a few new features, including boolean and phrase searching. In OS X 10.5, Spotlight can also act as a calculator and dictionary and a calculator.
If you activate Spotlight (Command-Space) and type a word that’s in one of the OS X dictionaries (AirTunes, for instance), you’ll see a Definition entry in the list of Spotlight results. The same thing happens if you enter a calculation (3+(5*15)/60); you’ll see a Calculator entry in the results list. The calculator is pretty smart, too, paying attention to order of operations as you enter your calculation.
While I find these two features useful, perhaps you don’t–who knows, maybe you’ve built your entire file organization system around a series of folders named 1+1=2, 2+3=5, etc., and you’re tired of seeing calculation results in Spotlight when you just want to find the folders. Whatever the reason, it’s relatively easy to disable the dictionary and/or calculator features in 10.5’s Spotlight.
Open Terminal (in Applications -> Utilities), and type one (or both) of the following commands to disable the dictionary lookup and calculation features, respectively (press Return after each command):
defaults write com.apple.spotlight DictionaryLookupEnabled NO
defaults write com.apple.spotlight DictionaryLookupEnabled NO
After executing one or both of the above commands, you need to restart the Spotlight process for the changes to take effect. You can do that by logging out and back in (the safest way to do it) or if you’re impatient, by running this Terminal command:
killall Spotlight
The above command kills the processes associated with Spotlight, which will then automatically restart. While this worked fine for me in testing this hint, if you do experience a problem (the Spotlight icon doesn’t come back, for instance), a logout and login cycle will fix the problem.
If you disabled these features and then decide you’d rather have them back–perhaps when you scrap your math-based folder naming system–simply repeat the original Terminal commands, but replace NO with YES. Restart Spotlight as above, and you’ll again see calculation and dictionary matches in your search results.