In chemistry, a nitride is a compound of nitrogen with a less electronegative element, attached together in a specific way. Nitrides are a large class of compounds with a wide range of properties and applications.
Most of the names for nitrides follow a simple pattern: the name of the element attached to the nitrogen, then "nitride". So, GaN would be gallium nitride.
There are some exceptions, however, for the compounds that has had a usual name before. For example, NH3 is not called hydrogen nitride, even if it is the most simple of this class of molecules, but it is still commonly called ammonia.