milestone

noun

mile·​stone ˈmī(-ə)l-ˌstōn How to pronounce milestone (audio)
Synonyms 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
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.
Despite a few glimmers of good feeling, today's fierce political divisions have redefined a milestone that has often been marked by unity and optimism, at least for a moment. Susan Page, USA Today, 22 June 2026 Even in the modern era, few mortals can achieve such milestone anniversaries, at least not without the help of a cryogenic freezer. Hillary Busis, Vanity Fair, 22 June 2026 This milestone required sustained partnership between the state of Maryland, the federal government, local communities and private industry. Wes Moore, Baltimore Sun, 22 June 2026 SpaceX just notched a remarkable launch-dominance milestone. Mike Wall, Space.com, 22 June 2026 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 23 Jun. 2026.

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

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