mile·stone | \ˈmī(-ə)l-ˌstōn \

Definition of milestone 

1 : a stone serving as a milepost (see milepost sense 1)

2 : a significant point in development Graduating from college was an important milestone in her life.

Illustration of milestone

Illustration of milestone

milestone 1

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Examples of milestone in a Sentence

the new drug was regarded as a milestone in the treatment of heart disease

Recent Examples on the Web

This year is special because Saint Sophia is marking a major milestone. Gloria Casas, Elgin Courier-News, "Saint Sophia’s Greek Fest shares sounds, tastes and feel of Greece at Elgin church," 14 July 2018 The opening of the Center for Advanced Pediatrics marks a key milestone in our North Druid Hills Campus journey. Joshua Sharpe, ajc, "CHOA announces opening date for first part of massive expansion," 12 July 2018 The couple had been engaged for a year before the announcement, The Mirror reports, but the day still marks a huge milestone in their relationship. Kayleigh Roberts, Marie Claire, "Prince Louis' Christening Date Has Been Set and It's On a Day That's Very Special to the Queen," 7 July 2018 An end to Papadopoulos’s involvement would mark a milestone in the investigation, which formally opened after Australian officials alerted the FBI to an unusual interaction with him in London in July 2016. Spencer S. Hsu, Washington Post, "Former Trump campaign aide Papadopoulos to be sentenced Sept. 7 in Russia investigation," 28 June 2018 Gabrielle Union has famously worn nearly every conceivable hair look, and now the beauty-chameleon actor just got a gorgeous new bob that marks a major milestone in her life: This is the first time Union's own hair has ever gotten a major chop. Lindsey V Thompson, Allure, "Gabrielle Union Just Cut Her Hair Into a Short Bob for the First Time Ever," 22 June 2018 The 10 millionth patent also marks another milestone in the history of the USPTO: the first patent cover redesign in 30 years. Renae Reints, Fortune, "Take a Look at the 10 Millionth U.S. Patent (And the First)," 20 June 2018 The event marked a significant milestone in the recovery from last year's shooting at a practice for the game that nearly killed one of the most powerful members of Congress. Ryan Nobles, CNN, "Scalise records first out in return to Congressional Baseball Game for Charity," 14 June 2018 More than 1,430 students from Naperville Central and Naperville North received high school diplomas during ceremonies at their respective football stadiums, followed by fireworks displays to mark the milestone. Jane Donahue, Naperville Sun, "School gifts, popular colleges and other things to know about Naperville's five graduating classes," 31 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'milestone.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of milestone

1662, in the meaning defined at sense 1

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Statistics for milestone

Last Updated

17 Oct 2018

Look-up Popularity

Time Traveler for milestone

The first known use of milestone was in 1662

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More Definitions for milestone



English Language Learners Definition of milestone

: a stone by the side of a road that shows the distance in miles to a specified place

: an important point in the progress or development of something : a very important event or advance


mile·stone | \ˈmīl-ˌstōn \

Kids Definition of milestone

1 : a stone by the side of a road showing the distance in miles to a given place

2 : an important point in progress or development His discovery was a major milestone in scientific research.

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