noun

precursor

pree-KUR-ser/priˈkɜːrsər/

Something that comes before and helps lead to the development of something else.

The gathering dark clouds are a precursor to the heavy downpour.

A compact before-and-after weather comparison shows gathering dark clouds preceding a heavy downpour over the same small landscape, illustrating a precursor that signals what follows.
Etymology

A precursor is literally a forerunner—one that runs ahead. That image extends to something appearing before an event and indicating its approach.

In context

This Week in Science (TWIS)154:08
a food that has a precursor that then gets broken down and built up and turned into something else that gets used in the body
Why Friendliness is Fabulous

More examples

  • Her short story became the precursor to a bestselling novel.
  • Small neighborhood meetings served as precursors to the citywide campaign.
  • The body uses this compound as a precursor to vitamin D.

Forms

precursor · precursors

Similar words

forerunner
Emphasizes an early version that anticipates something later.
predecessor
Something replaced by another, without necessarily contributing to its development.
antecedent
An earlier event or condition, not necessarily a developmental step.