It means nonce, but without using the letter E, either for comedic effect or to refrain from saying the full word.
May also be used to describe someone that is not a full nonce, but is close.
An individual who uses a dog for any of the following: 1) sexual contact, 2) fouling public places with faeces, 3) placing faeces where children play, 4) imposing their dog(s) onto members of the public, 4) causing noise nuisance.