Which term describes an ongoing illness that is slow or gradual in onset with no known cure?

The term that describes an ongoing illness that is slow or gradual in onset with no known cure is "chronic." Chronic illnesses are characterized by their prolonged duration and can often be managed but not completely cured. This means that individuals with chronic conditions may experience symptoms over long periods, which can affect their daily lives. The slow or gradual onset indicates that the disease develops progressively rather than suddenly.

Acute conditions, in contrast, are typically severe but short-term, often requiring immediate care. Terminal illnesses refer to diseases that are expected to lead to death, usually within a limited time frame, indicating a more immediate and dire prognosis. Recurrent conditions occur in episodes, where symptoms may resolve but come back over time, rather than being continuously present. Understanding these distinctions helps healthcare providers and caregivers tailor their approach to managing different types of health issues.