It is Dodger, but I thought Terry used Cockney slang in other books too??? E.g. in Going Postal, where Oliver Groat uses the arrhythmical Cockbill Street slang, and it contrasted with Cockney slang?
Nonrhyming slang actually is pretty close to the current version of Cockney rhyming slang, as the people I know who have used it tend to drop the rhyming word. For instance, "feet" used to be called "plates of meat", but now they just say "plates."
It was central to Nanny Ogg's soul that she never considered herself an old woman, while of course availing herself of every advantage that other people's perceptions of her as such would bring.