milestone

noun

mile·​stone ˈmī(-ə)l-ˌstōn How to pronounce milestone (audio)
Synonyms of milestonenext
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.
Wall Street’s artificial intelligence boom is edging toward a new milestone as one of the industry’s most valuable startups takes steps toward a potential public debut. Aamir Khollam, Interesting Engineering, 1 June 2026 Many professionals spend years chasing the next milestone. Bybryan Robinson, Forbes.com, 1 June 2026 That milestone at the ASCO meeting reflects the dizzying growth of China’s biotechnology sector. Ed Silverman, STAT, 1 June 2026 Kansas City Royals starter Michael Wacha reached a career milestone against the Texas Rangers on Sunday afternoon. Jaylon Thompson, Kansas City Star, 1 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 2 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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