腐蚀 (fǔshí) is a verb meaning 'to corrode' in a physical sense—such as when acid eats away at metal—or 'to erode morally', describing the gradual, damaging influence of negative ideas, habits, or environments on a person’s character or values. The first character, 腐 (fǔ), means 'rotten' or 'decayed', suggesting decomposition; the second, 蚀 (shí), means 'to eat away' or 'to erode', often used for gradual loss or damage. Together, they vividly convey a slow, destructive process—whether of materials like iron rusting in moisture or of integrity undermined by prolonged exposure to corruption or temptation.

This word appears frequently in scientific contexts (e.g., chemistry, engineering) and in moral or social commentary (e.g., media criticism, political discourse). It carries a strong negative connotation and is rarely used in neutral or positive settings. While it can describe literal chemical corrosion, its figurative use—especially in discussions of ethics, youth development, or institutional decay—is equally common and powerful in modern Chinese writing and speech.