Eijiro is the "big dog" of Japanese-English dictionaries. It's actually a suite of dictionaries--the two main ones are Eijiro (yes, the same name as the whole package), which has over 1.7 million English-to-Japanese entries, and Waeijiro, which has almost 2 million Japanese-to-English entries. The suite also includes separate dictionaries of example sentences, abbreviations, and acronyms (these are folded into Eijiro and Waeijiro in the JLT version). Eijiro was made and continues to be updated by the Electronic Dictionary Project (EDP), a society for professional translators; as such, it's especially rich in difficult and obscure terms, colloquial expressions, and technical terms. When a conversation reaches an impasse over a critical word or expression, the electronic dictionaries come out--it's common for me to quickly find it in Eijiro or Waeijiro, while my Japanese friends pounding away on their high-end Wordtanks and Ex-Words come up dry ("come up dry" is in Eijiro!). Not only does Eijiro have a huge number of words and phrases, it also gives you a good bit of information about them, especially example sentences showing the meaning more precisely and how to use the word or expression grammatically.
Eijiro is a tremendous resource, but it was designed for Japanese users (for example, only a small number of Japanese words in the English-to-Japanese entries and NONE in the Japanese-to-English entries have yomigana showing you how to pronounce the word). For those of us who are NOT native Japanese speakers, the JLT version of Eijiro is a huge improvement over the original. The biggest advantage: yomigana for almost every word. This, in turn, means two things.
The current JLT system consists of two dictionaries, Eijiro for English-to-Japanese lookups and Waeijiro for Japanese-to-English. Here are a few screenshots--English-to-Japanese on the top (note the dictionary name "Eijiro" in the bar at the top of the screen) and Japanese-to-English on the bottom ("Waeijiro"). For an explanation of how the dictionary program itself works, please see the EBPocket page. Note the yomigana next to kanji-containing words and the example sentences.
And here's what you get when you look up a Japanese word (click any to see it in full VGA):
You'll find the word whether you've written kana or kanji into the find box.
Note that I've sized the images here to appear about the same physical size as the Axim or iPAQ's screen (depending on your monitor, of course); however the actual PDA screen squeezes a full 480x640 pixels into that space, so it's much sharper and easier to read (more pixels in the same size=higher resolution). You can click each image to see the actual 480x640 pixels you'd get on the screen of an Axim or other VGA PDA, although because the image will then be much larger than on the Axim screen it still won't look quite as sharp as the real thing. And of course you can change the text size to be larger or smaller, too, which will also affect legibility (these shots are from the old version of Eijiro, without yomigana).
Basically, enter a word in the search window and tap Find (you can see that in the first part of the animation on the right, below). Pretty easy, huh? The key thing to remember is that English words are Eijiro and Japanese in Waeijiro--if you enter, say 惑星 or わくせい into Eijiro you won't find anything; ditto if you enter an English word into Waeijiro. See the general instructions for particulars on how to enter text and see the EBPocket page for particulars on using the software. Both Eijiro and Waeijiro are huge, so I don't recommend that you use the Full search type in them (Full searches the entire text, not just the index of keywords--and when the text is hundreds of thousands pages long, that can take quite a few minutes; all the other search types take between 0.1 and 2 seconds.
The JLT version adds one more feature that makes Eijiro dramatically more useful. In the Search Type pull-down menu to the right of the Find button at the top, you can choose Cross as a search type. You can enter one or more words, separated by spaces, in English or Japanese, and Cross Search will find all entries with those words anywhere in the keyword. Trust me, however useful you think this sounds, it's even more useful. It's great when you're looking for a phrase and aren't sure exactly how to word it. It's great when you're trying to find an example sentence to show the grammar of how to use something. For example, recently I wanted to see what particle and word order to use in saying "compare A with B," so I did a cross search of "compare with" and found both a general entry explaining the grammar and several more particular, real-life example sentences. You can enter "cat dog" to find out how to say "it's raining cats and dogs." You probably won't use it much at first as you get used to the dictionaries in general, then you'll try it out once in a while, and soon--especially as you advance in ability and your needs become more complex--you'll find yourself using cross search more and more often, in ways even I haven't thought of yet. Especially with official correspondence, I can often compose an entire letter with sentences I've found this way (lazy, but useful!). Note that, for Japanese searches, you can't enter hiragana or katakana in a Cross search.
A side effect of adding the yomigana to the dictionary as a whole is that, if a word can be pronounced more than one way, all the different pronunciations will be added wherever that word appears. This doesn't really affect the entries for inividual words too much, but in some entries for example sentences, both readings will be shown, even though only only of them really makes sense in context. Fortunately you won't run into this too often, and when you do you can simply jump to Edict to see which pronunciation is right in that context. Where there are two readings for a word, if you do a search for the word by reading (entering hiragana to search in Waeijiro), the way the software works it puts that reading right at the top of the screen--meaninig that everything above that poiint in the entry will be off to the top of the screen. When that happens, you'll see a green upward-pointing arrow on the left side of the first line of the definition--tap it and the program will show you the whole entry, starting at the top.
Eijiro is made for translators, so it assumes you already know basic vocabulary. Sometimes if you search for a fairly basic word, you won't find it--in that case, look in Edict. Sometimes, too, you'll look up a basic English word like "dog" and, because it assumes any Japanese who's gotten through junior high school knows that "dog" is "犬｛いぬ｝," it gives you more colloquial meanings instead of just the straight one. You can always spot this, because the definition will look too complicated for the simple term, and it'll be followed by a number of subsidiary phrases in which "dog" is translated as "犬｛いぬ｝." Hard to explain and it doesn't come up that often (and never anything but the simplest vocabulary), but when it does it's easy to spot. Having both dictionaries gives you just about every Japanese word you're ever likely to encounter.
JLT conversion of Eijiro dictionaries and sale on this website by written permission of EDP (obtained August 11, 2008). "Eijiro" is a registered trademark of Sachiko Michihata. The JLT version of Eijiro is temporarily unavailable while it's being updated. The latest version will be released in June 2013.
While the dictionary data in Eijiro comes from EDP, the JLT version has been heavily altered. JLT takes responsibility for any errors in the data. Further, the version of Eijiro described here is available ONLY from this site. The original, unaltered version of Eijiro is sold as a download from the website of EDP, the group that made and continues to maintain it. The download costs 1980 yen--certainly the biggest bargain around. Here's a hint for getting through the online payment forms: use rikaichan on Firefox to show what to enter where. After paying, you'll be given a link to download the files. You'll get all the dictionaries in both PDIC format (for those of you using WDIC on a Palm OS PDA) and text format. The PDIC version from EDP has no yomigana whatesoever, and the text version (and any other version you build out of that) has yomigana for only a limited number of Japanese words in E-to-J entries only (none in J-to-E entries). If you want Eijiro with full yomigana, Japanese Language Tools is the only place you'll find it.Because of all the work that's gone into Eijiro (and I'm referring to the that of the original makers, too, not just my own) and because any piracy by my customers could endanger my ability to offer Eijiro, I put a unique identifying code into every copy I sell and I regularly check all the downloading sites. If one of my customers posts a copy of Eijiro to any file sharing site, I will be able to prove who bought that copy and I will turn that information over to Eijiro's lawyers. Sorry if that sounds harsh, but it's necessary. The JLT version of Eijiro includes no spyware or malware, no tracking software, and no DRM tricks that impede your use of the dictionary.
May 19, 2013: The JLT version of Eijiro is temporarily unavailable while it's being updated. The latest version will be released in June, 2013.
Once the new version is released, it will be included in the JLT Complete System. You'll also be ablet to purchase it separately by download for use on other devices, including Windows and Mac computers, Android phones and tablets, iPhones and iPads, and any other platform that offers Japanese text capability and an EPWING-compatible dictionary app or program. After the JLT Complete System, the next-best platform for a Japanese dictionary is the Samsung Galaxy Note--anything else is at best a very distant third.