Online Dictionaries
Here are some good online dictionaries for learners of English.
Tip: While you're studying online, open an online dictionary in another browser window and move it to the side of your desktop. Then you can quickly look up words and get back to reading/listening as quickly as possible.
Tip: Many learners find it useful to use a bilingual dictionary the first time they meet a word, so they can get a quick, clear idea of the basic meaning. Then, as they continue studying or meet the word again, they use an English-English dictionary to expand their knowledge of the word and its use.
Cambridge provides a variety of dictionaries at one site. Great for students of different levels.
Longman Dictionary of Contemporary English
Good English-English learner's dictionary.
This bilingual dictionary's strength is the many examples it provides. Includes English-Japanese & Japanese-English.
Easy-to-use bilingual dictionary. English-Japanese, Japanese-English, Kanji dictionaries included. Also listen to pronuncation models.
Online Reading Support
Rikai.com Great Help for Reading Online!
Paste an English text or the URL for a page you want to read into the window and hit "go." You'll see the text or webpage in a new window. It'll look the same, but this time, when you pass your cursor over a word, you'll automatically see a "pop-up" definition in Japanese. You can also do Japanese to English.