Flaring up is a term used to describe a sudden and intense increase in a particular emotion or physical sensation. This phrase can be replaced with many synonyms depending on the context, including boiling over, erupting, igniting, inflaming, kindling, sparking, and exploding. Emotional flaring up can be associated with anger, frustration, or passion, while physical flaring up can refer to pain or inflammation. In both cases, the underlying concept is that something has reached a breaking point and is now experiencing a sudden and intense surge. By using alternative synonyms for this phrase, writers can add variety and emphasis to their writing and convey the full extent of the situation.