Meaning – Police. This expression is used to describe the police in an informal way. The Old Bill can be used to describe police collectively or in a general way.
In the UK there are a number of different slang expressions that can be used to refer to the police. Many of these expressions are impolite, but the expression Old Bill infers a certain amount of respect. This expression is informal but friendly.
“Hey boys, you better watch out. I’ve just seen the Old Bill down the road.”
Is there a similar expression for the police in your country?