AnswerLinks is a plugin that uses an API at Answers.com to auto-suggest links to definitions, names, technical terms and obscure language for words in your blog posts. AnswerLinks is a quick and simple way to provide more information for your readers.
Only words that you confirm will be linked to definitions, giving you full editorial control. There are two ways to do this; you can step through the terms one by one using “Link” and “Don’t Link” buttons (similar to the way a spell checker works), or you can simply use the list of links on the side and check the boxes for the terms you want to link.
This was started as a WordPress.com project, but is also available as a downloadable plugin for self-hosted/WordPress.org users.