The word 痛苦 is formed by combining two characters, each representing a distinct yet complementary aspect of suffering. The first character, 痛, primarily conveys a sharp, acute, or physical sense of pain or ache. The second, 苦, evokes a deeper, more lingering sense of bitterness, hardship, or mental anguish. Together, they do not simply add their meanings but fuse them to create a holistic and intensified concept of suffering that encompasses both immediate, sensory pain and prolonged, emotional distress.