mile·​stone | \ ˈmī(-ə)l-ˌstōn How to pronounce milestone (audio) \

Definition 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.

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Illustration of milestone

milestone 1

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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

Welcoming one of life's most momentous milestones with an unapologetically strong and sensual attitude, Kunakey exudes serious radiance. Lauren Valenti, Vogue, "This French Model’s Beach Snaps Are Pregnancy Body Confidence at Its Finest," 1 Feb. 2019 One of those momentous milestones included Monsta X snagging a slot on this year's Jingle Ball tour. Jeff Benjamin, Teen Vogue, "Monsta X on Proving Themselves in the United States and Meeting Some of Pop's Biggest Names," 26 Dec. 2018 But there are plenty of harder milestones ahead, ones that proved to be stumbling blocks for other warplanes such as the F-22 Raptor. Joe Pappalardo, Popular Mechanics, "New U.S. Secret Bomber Program Passes Critical Design Review," 6 Dec. 2018 This cycle included a series of milestones: Reps.-elect Ayanna Pressley and Jahana Hayes were the first African-American women Massachusetts and Connecticut had ever elected to the House, respectively. Li Zhou, Vox, "This year’s elections are changing Congress for the better," 6 Dec. 2018 That’s just one of many milestones to come out of this race. Kayla Webley Adler, Marie Claire, "The 2018 Midterm Elections," 6 Nov. 2018 The Leaping Bunny certification of COVERGIRL marks a new milestone in this area as the largest makeup brand to be certified cruelty free after having met our rigorous criteria. Jenna Rosenstein, Harper's BAZAAR, "Covergirl is Now Cruelty-Free Certified by Leaping Bunny," 6 Nov. 2018 As Chicago’s minimum wage jumps to $12 per hour Sunday, from $11, restaurant owner Laura Gutierrez Ramos is marking the milestone with a shrug. Alexia Elejalde-ruiz,, "Chicago's minimum wage is about to jump to $12 per hour. Who are the winners and the losers?," 29 June 2018 The milestones for women in politics this year are undeniable: more women on the ballot than ever before, a record number of women elected to Congress, and historic firsts like the first Muslim women in Congress, Rashida Tlaib and Ilhan Omar. Anna North, Vox, "Women made historic gains in 2018. But in so many ways, it was still the Year of the Man.," 27 Dec. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'milestone.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of milestone

1662, in the meaning defined at sense 1

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Last Updated

7 Mar 2019

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Time Traveler for milestone

The first known use of milestone was in 1662

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English Language Learners Definition of milestone

: a stone by the side of a road that shows the distance in miles to a specified place
: an important point in the progress or development of something : a very important event or advance


mile·​stone | \ ˈmīl-ˌstōn How to pronounce milestone (audio) \

Kids Definition of milestone

1 : a stone by the side of a road showing the distance in miles to a given place
2 : an important point in progress or development His discovery was a major milestone in scientific research.

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of or relating to a parable or parabola

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