When a situation or an economy takes a nose dive, it experiences a sudden and steep decline. In such cases, there are several synonyms that can be used to describe this sudden downturn. For instance, words like plummet, slump, drop, crash, sink, collapse, and nosedive can be used interchangeably to indicate a significant loss in value or decline in performance. These words convey a sense of urgency and alarm, indicating the severity of the situation. Whether in the context of finances, sports or relationships, using synonyms for 'nose dive' can add depth and nuance to one's writing, while also providing an efficient and effective method of describing sudden downturns.