What does fulgurant describe?

Fulgurant is a term that specifically refers to something that occurs suddenly and with intensity, much like a flash of lightning. This descriptor is often used in medical contexts to describe conditions or events that arise rapidly and can be quite severe, such as fulgurant appendicitis, which indicates a sudden and severe onset of symptoms.

The emphasis on severity and suddenness in the definition aligns with the dynamic and impactful nature of events described by the term. This is why it is the correct choice for what fulgurant represents. The other options describe changes or occurrences that are either slow, consistent, or weak, which do not reflect the immediate and intense nature implied by the word fulgurant.