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

An Academy of Holy Angels senior hit a basketball career milestone earlier this month. —Marielle Mohs, CBS News, 27 Jan. 2026

Bank of China’s Pivotal Role and Future Innovations Zhu Jing of Bank of China (Hong Kong) detailed the milestones leading to the MOU. —Sean Lee, Forbes.com, 27 Jan. 2026

The return represents a milestone not just for education operations but for a community that has navigated displacement, disruption and recovery together. —Daily News, 27 Jan. 2026

A couple off the helpers were of the milestone variety. —Steve Conroy, Boston Herald, 27 Jan. 2026

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