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.
The milestone also brought to mind a funny moment William shared years ago about George’s birthday. Janine Henni, People.com, 23 July 2025 Leading critics of the projects hailed Tuesday’s vote as a milestone in the fight to rein in San Diego’s unusually aggressive incentive for backyard apartments, which are formally called accessory dwelling units, or ADUs. David Garrick, San Diego Union-Tribune, 23 July 2025 The milestone comes about 7 months after the agency announced sales had surpassed the $7 billion mark, and on the heels of record-setting monthly sales in the most recent January, April, and May. Matthew Medsger, Boston Herald, 22 July 2025 The company has hit some milestones but has also been beset by problems, as three of the rockets launched from Texas this year have exploded—disrupting air traffic and raining debris on beaches and roads in the Caribbean and Gulf waters. ArsTechnica, 22 July 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 26 Jul. 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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