Encyclopedia Lite is a WordPress encyclopedia / lexicon / glossary / dictionary plugin by dhoppe, that enables you to create, manage and present a knowledge base. Completely coalesced with your WordPress and fully compatible with all the cool publishing tools you like.
In the Lite Edition of the plugin you can take a look around and you try out everything. On several places in the plugin you will find a notice that this function is included in the Pro Version only. There is no support available for the free Lite Version.
Main features
Create, manage and structure your Terms as
Encyclopedia, lexicon, glossary, Wiki or dictionary
Use tags and categories to classify your terms
Automatic association of related terms
Completely translatable – .po file is included
Supports the WordPress Theme Template hierarchy
Supports user defined HTML templates
Supports WordPress user rights and capabilities
Supports RSS Feeds
Clean and intuitive user interface
Multiple Widgets to display the terms and taxonomies of your Encyclopedia
No ads or brandings anywhere – perfect white label solution
Download and info: http://wordpress.org/extend/plugins/encyclopedia-lexicon-glossary-wiki-dictionary/