TIdDICTServer = class(TIdCmdTCPServer);

TIdDICTServer is a TIdCmdTCPServer descendant that implements a server for the Dictionary Server Protocol, as described in the Internet Standards document: 

RFC 2229 - A Dictionary Server Protocol  

The Dictionary Server Protocol (DICT) is a TCP transaction based query/response protocol that allows a client to access dictionary definitions from a set of natural language dictionary databases. 

TIdDICTServer uses an event-based architecture that provides event handlers for the following DICT protocol commands: 

TIdDICTServer also provides the OnCommandOther event handler to respond to unknown DICT commands, or DICT protocol extensions. 

TIdDICTServer does not provide an implementation of the event handlers. The application should assign procedures to the event handlers to respond to event notifications, or the result code 500 with the error message RSCMDNotRecognized will be generated.