Was Jack the Ripper a pseudonym?

Answer 1

"Jack the Ripper" is a pseudonym in that it is a false name which conceals the true identity of the person to whom it refers. However, in this case it would be more accurately described as a soubriquet, as it is a type of nickname imposed by someone other than the person to whom it refers.

The murderer now generally referred to as "Jack the Ripper" was originally known as "The Whitechapel Murderer". An letter signed "Jack the Ripper", purportedly written by the killer, was sent to the press during the series of murders and the press latched onto it as a suitably dramatic name by which to refer to the murderer. There is no evidence to conclusively prove that the author of the letter signed "Jack the Ripper" was in fact the murderer, and the police, press and others received hundreds of letters purportedly written by the murderer over this period.