milestone

noun

mile·​stone ˈmī(-ə)l-ˌstōn 

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

• milestone 1

Synonyms

• climacteric
• climax
• corner
• landmark
• milepost
• turning point
• watershed

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

The milestone was noted in the measurement firm’s latest edition of The Gauge, a monthly snapshot of TV viewership. —Dade Hayes, Deadline, 17 June 2025

There was a chance the library might not have made it to the half-century milestone after structural damage to its home at 555 N. La Grange Road forced officials to undertake a major building renovation. —Hank Beckman, Chicago Tribune, 17 June 2025

Rack’s milestones in recent years have been defined by a series of strategic acquisitions. —Jon Stojan, USA Today, 17 June 2025

The milestone for streaming services coincides with the four-year anniversary of Nielsen’s first Gauge data release in May 2021. —Rick Porter, HollywoodReporter, 17 June 2025

Word History

First Known Use

1662, in the meaning defined at sense 1

Rhymes for milestone

• acetone
• anglophone
• baritone
• bourguignon
• buspirone
• chaperon
• chaperone
• cobblestone
• collarbone
• cornerstone
• cortisone
• dictaphone

Kids Definition

milestone

noun

mile·​stone ˈmī(ə)l-ˌstōn 

1

: a milepost made of stone

2

: an important point in progress or development