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

Synonyms of milestone

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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.
SpaceX is believed to be targeting mid-September for Flight 14, which will be a big milestone in Starship's development — the vehicle's first-ever orbital trip. — Mike Wall, Space.com, 29 Aug. 2026 Trump faces mounting pressure to address high gas prices as the war in Iran on Friday reached a six-month milestone with no conclusion in sight. — Aamer Madhani, Los Angeles Times, 29 Aug. 2026 Once fully operational—a milestone targeted for January 2027—Roman’s science observations should finally begin. — Adam Kovac, Scientific American, 29 Aug. 2026 In addition to these milestones, this will be the ninth overall launch by the Ariane 6 program, which was developed by the European Space Agency and is now operated by Arianespace. — Eric Berger, ArsTechnica, 28 Aug. 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

Rhymes for milestone

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Browse Nearby Words

Milesian tale
milestone
mile-ton
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Cite this Entry

“Milestone.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/milestone. Accessed 1 Sep. 2026.

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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
Last Updated: - Updated example sentences
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