Primarily used in medical or formal contexts to describe a life-threatening or very serious condition. Often appears in phrases like 重篤な状態 or 重篤な疾患.
The patient was taken to the ICU in critical condition.
If left untreated, this disease can cause serious complications.
重篤 describes a serious or severe symptom or illness (common in clinical/medical documents), whereas 危篤 specifically means the person's life is in immediate danger of ending.
disruptive mood dysregulation disorder; DMDD
Compound of 重 (heavy, serious) and 篤 (grave, serious). The kanji combination reinforces the meaning of extreme severity, typically in a medical context.