The phrase "had one nose grindstone" is an idiomatic expression that means someone is focused and determined to work hard or achieve a goal. Some synonyms for this phrase include "nose to the grindstone," "working hard," "focused on the task at hand," "determined," "driven," "resolute," "tenacious," and "persistent." These words all convey a sense of dedication and perseverance towards accomplishing something difficult or challenging. They can be used interchangeably with "had one nose grindstone" to describe someone who is pushing through obstacles, putting in long hours, and staying committed to their objectives. Overall, these synonyms capture the essence of hard work and effort in pursuit of a goal.