www.thefreedictionary.com/
Get definitions, synonyms and more at TheFreeDictionary.com, a site that
serves up a wealth of reference material.
In addition to its dictionary and thesaurus, the site offers computing,
medical, legal and financial dictionaries. It also features acronym and
idiom dictionaries, plus the Columbia Encyclopedia and Wikipedia. When you
search for something, you get results from all these sources. This can make
for some rather text-heavy pages, but there's no question this is an
invaluable tool for students, researchers and other answer-seeking users. It
even makes for a worthwhile home page, as you can add bookmarks, subscribe
to RSS feeds and arrange content just by dragging and dropping.
source: www.lifehacker.com/