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 of milestone

• climax
• landmark
• watershed
• corner

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

In 2024, Caitlin Clark’s rookie season helped the WNBA hit milestone TV and attendance figures. —Sean Gregory, Time, 10 Dec. 2025

There's something so poetic about celebrating this milestone here — in a city that feels like pure inspiration. —Sabienna Bowman, PEOPLE, 9 Dec. 2025

Historically, free admission days at national parks take place on significant milestone dates or days when volunteer service at the parks is part of the tradition. —Michael Salerno, AZCentral.com, 9 Dec. 2025

Racing ahead of competitors The milestone also positions the robotics firm against domestic rivals. —Sujita Sinha, Interesting Engineering, 9 Dec. 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