1
general::
1. Enliven, make more interesting, as in They jazzed up the living room with a new rug, or They decided to include a comedy act to jazz up the program. 2. Modify so as to increase its performance, as in Peter wanted to jazz up his motorbike with a stronger engine. Both usages are colloquialisms from the mid1900s. Also see JUICE UP.
American Heritage Idioms
2
general::
Phrase(s): jazz someone or something up
to make someone or something more exciting or sexy; to make someone or something appeal more to contemporary tastes. • Let’s jazz this room up a little bit. • They jazzed up Donna till she looked like a rock star.
McGrawhill's American Idioms And Phrasal Verbs