Acute
The word acute is used to refer to any condition, disease, or disorder that:
- Develops quickly, i.e. has "rapid onset".
- Has severe symptoms.
- Does not persist for a long period of time, i.e. has a "short duration".
The word acute may also be used as an adjective to describe any intense symptom - such as severe pain.
For comparison, consider the meaning of the word: chronic.