Jam on is a phrase that means to add or apply something to enhance a situation, an object, or an action. Some synonyms for jam on include spruce up, improve, add to, spice up, revamp, embellish, adorn, enhance, decorate, and gussy up. These synonyms share the same concept of adding something extra to make it better. For instance, adding a touch of glitter to a plain dress can spruce it up, or adding a new component to a dish can spice it up. In essence, jam on synonyms are about adding flavor to life, be it in fashion, cuisine, or any other aspect of life that needs a little extra something to make it shine.