This is a denshi-jisho -- an electronic dictionary. It looks up words you highlight from a dictionary database.
The database used here is developed by the JMDict/Edict project and in all likelihood -- if you have studied Japanese using the Internet, you have encountered it before. If you have used Rikaichan or several other add-ons for Mozilla and Chrome, you have used this dictionary. If you have visited Jim Breen's site -- [...] you have used this dictionary. It shows up in many of the user implemented Japanese->English Internet dictionaries.
I have a paperwhite bought for studying Japanese. I'd be lost without a good e-dictionary. As far as I know this is the only implementation of the JMDict dictionary that runs in Kindle and in my opinion, it's an excellent implementation.
It works both on the Kindle and on the Android Kindle app.
To select this dictionary from a Kindle as your Japanese->English Dictionary, open a Japanese book within the Kindle, then open your settings menu->Device Options->Language and Dictionaries->Dictionaries->Japanese and select the '電子辞書 Japanese->English Dictionary'. Now when you highlight Japanese words within your book, they will be looked up using this dictionary. There exaamples of typical words looked up on the product page.
I've also tried it on several other Android tablets and so far it has worked on all of them. However it's hard to install on the other Android tablets.
To install on other Android tablets, you have to navigate to the Kindle directory, use the default dictionary on Japanese text to force it's download and copy this dictionary over the default dictionary. In my case, the default dictionary is the Japanese to Japanese Daijisen dictionary (see https://kindle.amazon.com/work/daijisen-x5927-x8f9e-japanese-edition-ebook/B005FNK020/B005FNK020/posts). To simplify this process I wrote a simple shell script. The easiest way I have found to use it is:
1) Install an Android terminal. These are available free on Google Play
2) Copy the script between the equals sign below to your clipboard.
3) Paste it in your terminal window to execute it. You will probably need to add a line feed at the end of your input.
# English->Japanese dictionary
if chdir /mnt/*/Android/data/com.amazon.kindle/files; then
if test -f $NewDict; then
if test -f $PrevDict; then
cat $NewDict > $PrevDict;
echo Replaced $PrevDict with $NewDict;
echo $PrevDict not found.
echo failed to find $NewDict;
echo Failed to find Kindle data directory;
If all works, you will see a message saying it replaced B005FNK020_EBOK.prc with B00FD9549A_EBOK.prc.
If it says it can't find your Kindle directory, your environment is different than mine. You will need to find where the Kindle data directory is.
If it fails to find B00FD9549A_EBOK.prc, you need to install the Japanese->English dictionary on your device.
If it fails to find B005FNK020_EBOK.prc, possibly you haven't tried to use a dictionary in your Japanese book yet. The other possibility is that your environment uses a different default dictionary than the Daijisen Japanese->Japanese dictionary. You need to determine which dictionary was downloaded and replace the PrevDict value with the correct ..._EBOK.prc value.
WARNING! You do this at your own risk. Your books are all backed up by Amazon so I don't think this script can hurt anything, and I've made it as simple as I can in hopes it is understandable. You should never do something like this unless you understand what you are doing!
I just now tested this script on my Nook HD+ (software version 2.11) and it worked. I have tested the script on a Nook Color, a generic 7" Android tablet and a Nexus 7 all running Android 4.3. I have not tried it on the KitKat release. It will probably work on a Kindle Fire but I haven't tried it.
This dictionary has been really useful for me. I hope you find it useful too.