Firefox's add-on dictionaries

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Firefox's add-on dictionaries

Post by Erik_Kowal » Fri Apr 11, 2008 9:57 am

The latest version of the Firefox browser ( comes with easy access to a whole bunch of online dictionaries: go to Tools > Mozilla Internet Dictionary. Selecting this opens a new window containing tabs for a number of English-English dictionaries that have been preselected by default. In my browser these are:

Merriam-Webster, Encarta, Longman, Chambers, Cambridge Advanced Learners, Wordreference, Ultralingua and OneLook.

However, this is just the tip of the iceberg. Selecting Preferences > Dictionaries opens a new window with check boxes that allow you to add a dozen more English dictionaries if you wish, as well as to deselect ones that are currently selected.

Meanwhile, on the left of the screen is a scratchpad that automatically records the words you have looked up during the current dictionary session so that you can easily go back to them. In addition, if you select a word in the scratchpad you can go to any of the dictionary tabs and see the corresponding entry (or entries) for that word.

The dictionaries are not limited to English-language ones.

Preferences > Dictionaries also enables you to select dictionaries for a large number of other language pairs, even unusual combinations like Albanian-Swedish or Estonian-English.

You can see a listing of the URLs of all the dictionaries (of which there are currently almost 500) at Help > Show Dictionaries.

More information about the dictionary project is available at, including a description of how to run the dictionary interface as a standalone application if this is desired, and how to add new dictionaries to the available selection.

By consolidating and integrating access to so many dictionaries within a simple, unified interface, Firefox's developers have created a convenient and powerful new tool for the casual user and professional linguist alike.

Ed. With foreign-language versions of Firefox, there are no dictionaries selected by default. You have to select them as described above.
Last edited by Erik_Kowal on Fri Apr 11, 2008 7:05 pm, edited 2 times in total.
Reason: Foreign-language versions
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