noun

1. a kind of music, originally improvised but now also arranged, characterized by syncopation, rubato, usually heavily accented rhythms, dissonances, individualized melodic variations, and unusual tonal effects on the trumpet, trombone, clarinet, saxophone, etc.: it originated with Southern blacks in the late 19th cent.
2. Slang a quality reminiscent of jazz music; lively spirit
3. Slang remarks, acts, concepts, etc. regarded as hypocritical, tiresome, trite, pretentious, etc.

Etymology: etym. uncert.: < ? Creole patois jass, sexual term applied to the Congo dances (New Orleans)

adjective

transitive verb

1. to speed up
2. Slang to fill with jazz qualities; make exciting or elaborate; enliven or embellish: usually with up

intransitive verb