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

Somali authorities see the closure as a milestone in the country’s ability to manage its own affairs. — ABC News, 2 Nov. 2026

In comparison, only 4% of participants receiving standard medical care reached the same milestone. — Khloe Quill, FOXNews.com, 2 Nov. 2026

That said, Antonelli’s rise to fame was much, much quicker, reaching the milestone that all F1 drivers set out to accomplish, yet most of them never do. — Jerry Perez, The Drive, 2 Nov. 2026

The milestone could help smartphones switch between conventional cell towers and satellites without dropping calls or losing data connections, bringing seamless satellite connectivity closer to commercial use. — Neetika Walter, Interesting Engineering, 2 Nov. 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