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

• 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

This announcement represents a major milestone in the software and hardware needed to efficiently process inference queries, disaggregating inference processing into two workloads with a GPU tailored for each in the case of long-context windows greater than one million tokens. —Karl Freund, Forbes.com, 9 Sep. 2025

An international crew will touch down using SpaceX's Starship lander no earlier than 2027, assuming technical and training milestones are reached. —Elizabeth Howell, Space.com, 9 Sep. 2025

American ’70s cinema was such an important milestone in cinematic history. —Scott Roxborough, HollywoodReporter, 9 Sep. 2025

His son, Chris Holbrook, remembers the house as a stage of sorts, where family milestones and gatherings of the city’s arts and culture leaders unfolded side by side. —Abby Montanez, Robb Report, 9 Sep. 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