“Jazz” clearly was a new word here, as the OED notes: “The existence of an article entitled ‘In praise of ‘jazz,’ a futurist word which has just joined the language’…suggests that the word was then a very recent innovation.”
Just a month later, on April 5, 1913, the same newspaper published a long article about the word “jazz,” noting its meaning and various spellings. “Jazz” clearly was a new word here, as the OED notes: “The existence of an article entitled ‘In praise of ‘jazz,’ a futurist word which has just joined the language’…suggests that the word was then a very recent innovation.”