If you haven’t looked up a word with Wordnik yet, its clean, slick design offers a given word’s:

• Dictionary definitions, from several sources
• Multiple real-world examples from historical texts
• Related words (thesaurus)
• Etymologies, also from several sources
• Audio pronunciation

Pretty useful so far, but those are also fairly standard dictionary features. Then Wordnik gets awesome:

• Real-time word use from Twitter
• Very cool bubble-graph of the word’s usage over time (going back to 1800!)
• Images from Flickr tagged with the word
• Anagrams
• Scrabble point score
• Community-uploaded word pronunciations

I’m also a big fan of their human-readable URLs. Here’s an example, from one of my favorite words:

http://www.wordnik.com/words/cacophony

The only downside is that if the word is somewhat rare—like abiogenesis, which I had to look up recently—then many of the features are truncated or gone. Another missing feature is a spelling suggestion tool; if you misspell a word, it doesn’t correct you or even give you an error message. In fairness to both criticisms, the project is clearly labeled as a beta.

Finally… yes, Wordnik contains dirty words, and yes, looking them up is every bit as juvenile and fun as it’s been since fifth grade.