What term is used for a sudden, severe condition that lasts briefly?

The term "acute" is used to describe a sudden and severe condition that has a rapid onset and typically lasts for a short duration. In a medical context, an acute condition can result from various factors such as injury, infection, or other health issues, and often requires immediate attention or treatment.

Acute conditions contrast with chronic conditions, which persist over an extended period and often result in long-term health issues. The term subacute can refer to conditions that are between acute and chronic, indicating a recovery phase that can last longer than an acute episode but is not fully chronic. Terminal specifically refers to diseases or conditions that are expected to lead to death, emphasizing the severity but not the brief nature of the condition. Thus, in the context of suddenness and duration, "acute" is the most accurate term.