Burns up is a phrase that is often used to describe a situation where something is consumed or destroyed by fire or intense heat. Nevertheless, there are a plethora of synonymous expressions that convey the same meaning as "burns up". For example, "incinerates," "roasts," "vaporizes," "engulfs," and "charbroils" are all alternatives to the phrase. Other phrases like "turns to ash," "ashes," "reduces to cinders," and "consumes entirely" can also be used to replace "burns up". Ultimately, the choice of word largely depends on the context and the imagery the writer intends to create.