watershed

An event or point after which an important situation changes greatly.

• The election was a watershed.
• Her first exhibition marked a watershed in her career.
• That ruling became a watershed for civil rights.

How to use it: a watershed in something (The election was a watershed in the country's history.); a watershed for someone/something (The discovery proved a watershed for modern medicine.)

Similar words: turning point, milestone

Common phrases: a watershed moment, watershed in something, a political watershed

An area of land where rain and streams flow into the same river, lake, or sea.

• This river drains a large watershed.
• Pollution upstream affects the entire watershed.
• The project protects forests in several watersheds.

Similar words: drainage basin, catchment

Common phrases: river watershed, watershed management, watershed protection

Important because it marks the start of a major change.

• It was a watershed moment.
• The watershed election changed the political system.
• Historians consider that agreement a watershed event.

Similar words: pivotal, epoch-making

Common phrases: watershed moment, watershed event, watershed election, watershed decision