- The definition of a milestone is a notable event that causes some change to occur or that marks a specific point in the development of a person or project.
- An example of a milestone is when the court makes a sweeping change in the civil rights law.
- An example of milestone is a person's 16th birthday.
Your twenty-first birthday is a milestone in your life.
milestone definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
- a stone or pillar set up to show the distance in miles to or from a specified place
- a significant or important event in history, in the career of a person, etc.
milestone definition by American Heritage Dictionary
- A stone marker set up on a roadside to indicate the distance in miles from a given point.
- An important event, as in a person's career, the history of a nation, or the advancement of knowledge in a field; a turning point.