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

Secretary of State Rubio and others have made no secret of the administration’s eagerness to complete a deal and, privately, officials acknowledge that the 100-day milestone looms large in White House thinking. —Eric Green, Time, 30 Apr. 2025

Ed [Sheeran] decided to add her as an opening act for the rest of his tour in Bahrain and Qatar, which is a big milestone for her. —Nick Vivarelli, Variety, 29 Apr. 2025

The rise of OpenAI's O3 is not just a technological milestone. —Dan Fitzpatrick, Forbes.com, 29 Apr. 2025

Read the full transcript of ABC News' milestone interview with Trump below. —Abc News, ABC News, 29 Apr. 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