precursor

noun

pre·​cur·​sor pri-ˈkər-sər  ˈprē-ˌkər- 

1

a

: one that precedes and indicates the approach of another

b

: predecessor

2

: a substance, cell, or cellular component from which another substance, cell, or cellular component is formed

precursory

pri-ˈkərs-rē 

-ˈkər-sə-

adjective

Did you know?

Precursor Has Latin Roots

With its prefix pre-, meaning "before", a precursor is literally a "forerunner", and in fact forerunner first appeared as the translation of the Latin praecursor. But the two words function a little differently today. A forerunner may simply come before another thing, but a precursor generally paves the way for something. So, for example, the Office of Strategic Services in World War II was the immediate precursor of today's Central Intelligence Agency, while the blues music of the 1930s and 1940s was only one of the precursors of the rock and roll of today.

Synonyms of precursor

• forerunner
• harbinger
• symptom
• herald
• sign
• angel

Choose the Right Synonym for precursor

forerunner, precursor, harbinger, herald mean one that goes before or announces the coming of another.

forerunner is applicable to anything that serves as a sign or presage.

the blockade was the forerunner of war

precursor applies to a person or thing paving the way for the success or accomplishment of another.

18th century poets like Burns were precursors of the Romantics

harbinger and herald both apply, chiefly figuratively, to one that proclaims or announces the coming or arrival of a notable event.

their early victory was the harbinger of a winning season

the herald of a new age in medicine

Examples of precursor in a Sentence

18th-century lyric poets like Robert Burns were precursors of the Romantics

a precursor of the modern eggplant

Recent Examples on the Web

People who are malnourished for an extended period of time, have diseases of the GI tract that impair the absorption of fat-soluble vitamins, and those whose diet is low in vitamin A or its precursors can develop a deficiency. —Mira Miller, Verywell Health, 8 Dec. 2025

Analysts said the letter could be a precursor to a hostile-takeover play by Paramount, which has moved aggressively in recent months under new CEO David Ellison’s leadership. —Brian Stelter, CNN Money, 5 Dec. 2025

Roman’s coronagraph is a critical precursor for more ambitious starlight-blocking hardware planned to fly on another future NASA mission, the Habitable Worlds Observatory, which could launch in the late 2030s to discover, image and study potential Earth twins around dozens of sunlike stars. —Claire Cameron, Scientific American, 4 Dec. 2025

The Film Independent Spirit Award nominations come one day after another major precursor awards body, the New York Film Critics Circle, voted to determine its annual list of winners, with One Battle After Another coming out on top as the group's Best Film of 2025. —Jillian Sederholm, Entertainment Weekly, 3 Dec. 2025

Word History

Etymology

Middle English precursoure, from Latin praecursor, from praecurrere to run before, from prae- pre- + currere to run — more at current entry 1

First Known Use

15th century, in the meaning defined at sense 1a

Rhymes for precursor

• bursar
• cursor
• mercer
• purser

Kids Definition

precursor

noun

pre·​cur·​sor pri-ˈkər-sər  ˈprē-ˌkər- 

1

: predecessor

2

: a substance or cell from which another substance or cell is formed

Medical Definition

precursor

noun

pre·​cur·​sor pri-ˈkər-sər  ˈprē-ˌ 

1

: one that precedes and indicates the onset of another

angina may be the precursor of a second infarction

2

: a substance, cell, or cellular component from which another substance, cell, or cellular component is formed especially by natural processes