Dragon

Dragon has two meanings within the Go community:

1. A dragon is a long connected shape spanning large areas of the board. Usually dragons share the same liberties in one long connected shape but in general they are just long shapes that span a large part of the board.

Black's Dragon  

This is a dragon without any stones around it. Usually dragons are mostly surrounded, and don't fence in much territory.

Then again you have dragons which are not technically dragons:

White 1 Completes a Dragon  

2. Dragon is the (short) name for a turn-based Go server: The Dragon Go Server (DGS).

Dieter: I don't know in English but in Dutch when we say een draak van een partij (a dragonlike game) we mean a very ugly game.

unkx80: Chinese players will call both of the examples above as dragons.