‘千辛万苦’ is a four-character idiom (chengyu) meaning ‘great hardships’ or ‘untold suffering.’ Literally, it combines ‘thousand’ (千), ‘bitterness/toil’ (辛), ‘ten thousand’ (万), and ‘suffering/pain’ (苦) — exaggerating the sheer quantity and intensity of difficulties endured. The structure emphasizes accumulation and extremity: not just one hardship, but countless layers of physical strain, emotional distress, and relentless obstacles.

This idiom is commonly used to describe arduous journeys, long-term struggles, or heroic efforts — especially when success is achieved only after enduring extreme adversity. It often appears in formal writing, speeches, or narratives about perseverance, immigration, scientific breakthroughs, or personal growth. While vivid and expressive, it carries a solemn, respectful tone and is rarely used lightly or humorously.