horse of a different color
有所不同的事物
口语·强调完全不同的事物
英文释义
Something that is completely different or unrelated; a separate or distinct matter
例句
That's a horse of a different color; we were talking about work, not hobbies.
典故来源
源自赛马中不同颜色的马代表不同事物，比喻完全不同的情况或话题。