Wordnik – An online dictionary aiming to collect all the words in the English language.

To learn about what is new from Wordnik, simply follow the updates on Twitter @Wordnik.

Twittonary is an easy way to learn about various Twitter related words, which in turn classifies it as a Twitter dictionary. The service includes 2 ways to search for the meaning of a Twitter related word; you can do so by either using the search box, or by viewing all the words that begin with a particular letter.

The service definition of Twitter related words is a collection of submissions by tweeple, meaning you can also contribute by adding a new word. Twittonary can definitely help you learn the terms used on Twitter, and can save some characters when tweeting, and as this is the subject, you can follow the tweets of the service @twittonary.

NinjaWords is a fast, accurate, and smart online dictionary. The service looks up words, "ninja style"; just type what you are looking for in the search box and watch it go.

Features:

• A really fast online dictionary
• Compare definitions by looking up many words on the same page
• Includes a history of your searches
• Can be added to Firefox and IE search toolbar

About:

NinjaWords is the creation of Phil Crosby, and that’s how Phil describes his site:

Ninjas are three things:

1. They’re smart
2. They’re accurate
3. They’re really fast

Ninjawords is based on these principles. Plus everyone likes ninjas.

Lexipedia is a great language tool that visually displays, the nouns, verbs, adverbs, adjectives, fuzzynyms, synonyms, and antonyms of any word you type in the search box, all displayed on a single page. Hovering over any spoke will bring up it’s definition and usage.

Lexipedia is available in English, Spanish, German, French, Dutch, and Italian. This service is powered by iSeek.

Definr.com is a fast, free dictionary based on Princeton’s open WordNet 2.0.

The website framework is Ruby on Rails. Looking up words in a dictionary is easy, so we do that with MySQL and cache the top 10,000 definitions in memory.

Doing word completion (a.k.a. auto-complete, auto-suggest, globbing) is not easy, at least not when you have to search through 200,000 words for every keystroke. So our word completion is done in a C module for Ruby, and the word completion server is separate from the rest of the site.

With the DefinrBot algorithm, we can do 190,000 word completions per second without caching, and that translates to about 10,000 completions per second once the Ruby layer is factored in.

Ajax dictionary and thesaurus.

A free online pronouncing dictionary with Instant Sound. American and British spellings, with alternative pronunciations. Sounds are fast, clear and completely natural, pre-recorded by native speakers. Answers the question “How do you say…?”. Also referred to as a pronunciation dictionary.