"Brings down the house" is an idiomatic phrase that means to cause great reactions from the audience during a performance. There are several synonyms for the expression that means nearly the same thing. Some of the synonyms include "kills it," "nails it," and "slays." These terms are commonly used in different contexts, like sports, fashion, and music, and all connote extraordinary success. Other relevant and similarly used expressions are "blows the roof off," "knocks it out of the park," and "brings the thunder," all indicating the impact of a particularly appealing or outstanding performance or presentation.