Definiția și Sensul lui "[keep|put] {one's} nose to the grindstone"

What is the origin of the idiom "keep one's nose to the grindstone" and when to use it?

The idiom "keep one's nose to the grindstone" originated from the practice of grinding tools on a grindstone, symbolizing the need to work diligently and stay focused without distractions. It is commonly employed in professional settings, such as workplaces or business environments, to encourage individuals to stay focused and diligently work on their tasks or responsibilities.