To make someone or something appear more exciting, interesting, dazzling, classy, or fancy. A noun or pronoun can be used between "snazz" and "up." You really should snazz yourself up a bit if you want to make a good first impression on your date. I decided to snazz up my outfit with a diamond necklace and some classy silk gloves. I always like to snazz up my popcorn with a bit of cinnamon and brown sugar.