mile·​stone | \ ˈmī(-ə)l-ˌstōn How to pronounce milestone (audio) \

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

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 Others are celebrating the possible milestone for the rights of the unborn. Washington Post, 5 May 2022 Monday marked an era-defining milestone for CNN, as new boss Chris Licht formally took the reins at the news network and now attempts a reboot after months of scandal and chaos. Andy Meek, Forbes, 3 May 2022 This is a very big, common question, and a huge milestone for people who are interested in getting married. Ryan Gajewski, The Hollywood Reporter, 1 May 2022 The show’s airing comes close to another milestone for the business: Cupbop will mark its ninth anniversary on Wednesday. Stefene Russell, The Salt Lake Tribune, 30 Apr. 2022 The acquisition represents a key milestone for the documentary industry as audience growth and business catch up to narrative. Jazz Tangcay, Variety, 26 Apr. 2022 The exhibition coincides with a major milestone for Britain’s longest-reigning sovereign. Sarah Kuta, Smithsonian Magazine, 18 Apr. 2022 The flight, which actually took place last December, marks a major milestone for the company. Rachel Cormack, Robb Report, 14 Apr. 2022 The vote also marks a major milestone for the Supreme Court and the federal judiciary, although Jackson's confirmation won't change the ideological balance of the court. Melissa Macaya, CNN, 8 Apr. 2022 See More

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.

First Known Use of milestone

1662, in the meaning defined at sense 1

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Time Traveler for milestone

Time Traveler

The first known use of milestone was in 1662

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Dictionary Entries Near milestone

Milesian tale



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Statistics for milestone

Last Updated

10 May 2022

Cite this Entry

“Milestone.” Dictionary, Merriam-Webster, Accessed 20 May. 2022.

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More Definitions for milestone


mile·​stone | \ ˈmīl-ˌstōn How to pronounce milestone (audio) \

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.

More from Merriam-Webster on milestone

Nglish: Translation of milestone for Spanish Speakers

Britannica English: Translation of milestone for Arabic Speakers


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