Bellsybabble is a fictional language of the Devil, which he makes up as he goes along. Writer James Joyce mentions it in the following postscript to a letter (containing the story now known as "The Cat and the Devil"), which he wrote in 1936 to his four-year-old grandson: The devil mostly speaks a language of his own called Bellsybabble which he makes up himself as he goes along but when he is very angry he can speak quite bad French very well though some who have heard him say that he has a strong Dublin accent.