指出 (zhǐ chū) means 'to point out' — it's a specific, deliberate act of calling attention to something, often a mistake or a fact. It's more focused than 指 (zhǐ 'to point at'), which is a simpler physical gesture, and less formal than 表明 (biǎo míng 'to indicate, make clear'), which is about stating something clearly. Use 指出 when you want to highlight or identify something specific.