5. Change your sources
Dictionary comes with a bunch of built-in reference sources. Select Dictionary > Preferences to see the list. Here you can determine which sources will show up when you search and what order they'll show up in. So, for instance, you could get rid of Wikipedia, add a Spanish language dictionary, or switch out the American English dictionary for a British English one.
Note that you have to be connected to the Internet to access Wikipedia. And what's the Apple dictionary, you may ask? It includes a glossary of Apple terms--helpful for those times when you're not interested in the type of apple you can eat.
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