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

Earth-impacting shrapnel from those primordial upheavals may have helped seed our planet with the precursors for life, delivering water and organic compounds from the dark, icy depths of the outer solar system. —Lee Billings, Scientific American, 18 June 2026

Scouts and Raiders is billed as telling the true origin story of the WWII commando unit of the same name, a precursor to the Navy SEALs, including its heavy recruitment of collegiate and professional football players. —Matt Grobar, Deadline, 18 June 2026

If Jackson ends up suing — a tort claim is a necessary precursor — that would be the fifth lawsuit against the city in less than two years. —Alex Brizee, Idaho Statesman, 17 June 2026

The records also show the company imported precursor chemicals used to manufacture fireworks, even though it was not licensed to manufacture fireworks. —Daniel Lempres, Sacbee.com, 16 June 2026

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