English Reference
noun · verb

milestone

n. · v.
US /ˈmaɪɫˌstoʊn/ UK /mˈaɪlstəʊn/ mile·stone UK spelling milestone's, milestone's

  1. 01 B2 Upper Intermediate

    n.an important event or stage in the development of something, like a person's life or a project.

    n.a significant stage or event in the development of something; often used metaphorically for personal, historical, or professional progress.

    Simple

    Learning to walk is a major milestone in a baby's development.

    In context

    The signing of the peace treaty represented a significant milestone in the diplomatic relations between the two neighbouring countries.

  2. 02 C1 Advanced AcademicTechnical

    v.to plan a project by breaking it into several big, important steps.

    v.to schedule or structure a project according to a series of specific, measurable goals or stages.

    Simple

    We need to milestone the software update to ensure we finish on time.

    In context

    The project manager decided to milestone the development phase to provide the stakeholders with clear evidence of incremental progress.

    Usage

    often used in project management contexts

Whether you’ve secured your first-choice place, are exploring options through clearing, or are still deciding what’s right for you, this is an important milestone and you should be proud of what you’ve achieved.

The Guardian· 13 Aug 2026

That long search reached a major milestone in 2023, when we identified an 84.1-meter-tall (276-foot-tall) Taiwania fir ( Taiwania cryptomerioides ).

ScienceDaily· 4 Aug 2026

From mile + stone. Compare Dutch mijlsteen (“milestone”), German Low German Mielensteen (“milestone”), German Meilenstein (“milestone”), Swedish milsten (“milestone”).

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Level B2 · Upper Intermediate
Frequency Frequent
Updated