铁石心肠 tiěshíxīncháng heart of stone Origin Definitions Defs Strokes Stroke Words Sentences Sents 铁石 鐵石 tiěshí firm and solid something extremely firm or solid, often used metaphorically to describe a person's resolve or heart心肠 心腸 xīncháng heart one's character, disposition, or intentions; one's state of mind when dealing with others or situations