Actually, I think I do understand what the question means. I think labrador means "pen" as in the common abreviation of state penitentiary - ie: a US prison.
In Tintin in America, Bobby Smiles uses the names of two famous "state pens" as expletives - Sing Sing and Alcatraz, between p.20 and p.24 (and later on as well, maybe.) eg: "Sing Sing! Redskins! How do I talk my way out of this one?", and , "Alcatraz! What a drop!"
As the question said, Bobby Smiles should be in a pen himself, but is quite far away from either of the real ones that he mentions. |