Jolly up is a British idiomatic expression that means to liven up or to cheer up. There are several synonyms to the word jolly up, including invigorate, enliven, animate, perk up, brighten, uplift, boost, energize, rejuvenate, and stimulate. These words can be used interchangeably to convey the same idea of bringing some life and energy to a situation or a person. Whether it is to jolly up a party, a meeting, or a friend who's feeling low, these synonyms can be useful in spicing up any situation and making it more enjoyable. So, next time you need to jolly up a situation, choose a synonym that best fits the mood!