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milestone

noun

mile·​stone ˈmī(-ə)l-ˌstōn How to pronounce milestone (audio)
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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
David Hoagland, acting deputy administrator for Defense Programs, said the CSA milestone shows that reforms intended to streamline design and manufacturing are starting to pay off. Kapil Kajal, Interesting Engineering, 25 Nov. 2025 California’s high-speed rail project is moving into a pivotal phase, with the state’s High-Speed Rail Authority outlining its anticipated 2026 milestones during the Board of Directors meeting on November 20. Ben Kelly, MSNBC Newsweek, 25 Nov. 2025 Doha marks the film’s Middle East and North Africa premiere, a milestone Jihan describes as emotional and overdue. Essie Assibu, Variety, 24 Nov. 2025 Until then, the deepening of ties between Saudi Arabia and the US will provide plenty of milestones, in both countries, to celebrate. Faisal J. Abbas, semafor.com, 24 Nov. 2025 See All Example Sentences for milestone

Word History

First Known Use

1662, in the meaning defined at sense 1

Time Traveler
The first known use of milestone was in 1662

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Cite this Entry

“Milestone.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/milestone. Accessed 27 Nov. 2025.

Kids Definition

milestone

noun
mile·​stone ˈmī(ə)l-ˌstōn How to pronounce milestone (audio)
1
: a milepost made of stone
2
: an important point in progress or development

More from Merriam-Webster on milestone

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