Why is it called jazz?

The word “jazz” probably derives from the slang word “jasm,”which originally meant energy, vitality, spirit, pep. The Oxford English Dictionary, the most reliable and complete record of the English language, traces “jasm” back to at least 1860: J. G. Holland Miss Gilberts Career xix.

How can I identify jazz music?

Although jazz listeners may not agree on which music and musicians qualify as jazz, at a basic level, you can identify jazz by a few distinguishing traits: swing and syncopation, improvisation, bent notes and modes, and distinctive voices.