OK, something I have also learned, though the only ones I ever listened to in NZ only transmitted weather.
However, way back in 1998 or thereabouts, NZCAA published a document that gave the definition as aerodrome weather information broadcast, and a google search of AWIB in NZ retains that definition.
Seems that the OP will need to write to CAA for the current official definition.
Not that it matters a sh!t unless sitting an exam where the result is contingent upon that answer being correct!