precursor

American  

[pri-kur-ser, pree-kur-] / prɪˈkɜr sər, ˈpri kɜr- /

noun

• precursors
  plural

1. a person or thing that precedes, as in a job, a method, etc.; predecessor.

   Synonyms:

   forerunner

2. a person, animal, or thing that goes before and indicates the approach of someone or something else; harbinger.

   The first robin is a precursor of spring.

   Synonyms:

   herald

3. Chemistry, Biochemistry. a chemical that is transformed into another compound, as in the course of a chemical reaction, and therefore precedes that compound in the synthetic pathway.

   Cholesterol is a precursor of testosterone.

4. Biology. a cell or tissue that gives rise to a variant, specialized, or more mature form.

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precursor British  

/ prɪˈkɜːsə /

noun

1. a person or thing that precedes and shows or announces someone or something to come; harbinger

2. a predecessor or forerunner

3. a chemical substance that gives rise to another more important substance

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Other Word Forms

Noun Inflected Forms

• precursors
  plural

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Etymology

Origin of precursor

1375–1425; late Middle English < Latin praecursor forerunner. See pre-, cursor

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Explanation

You've heard the old saying "Pride comes before the fall?" Well, you could just as easily say pride is a precursor to the fall. A precursor is something that happens before something else. You don't have to be a dead languages scholar to guess that this word springs from a Latin source — praecursor, "to run before." A precursor is usually related to what it precedes. It's a catalyst or a harbinger, leading to what follows or providing a clue that it's going to happen. Binging on holiday candy is a precursor to tummy aches and promises to exercise more. Draconian policies in unstable nations are often a precursor to rebellion.

Example Sentences

See Examples For:

precursor precursors

The precursor chemicals, which are only as flammable as sugar, are transported from Solugen to Odin using standard trucks, said Sean Hunt, co-founder of Solugen and Odin.

From The Wall Street Journal ● Oct. 27, 2026

They develop from immature precursor cells through a process called adipogenesis, or fat cell differentiation.

From Science Daily ● Oct. 24, 2026

The spool suit is the latest in a coordinated effort by California’s municipalities and the state attorney general’s office to throttle the bootleg gun industry by stanching the flow of its precursor components.

From Los Angeles Times ● Oct. 10, 2026

This week's "pre-COP" meetings in the Fijian city of Nadi are a precursor to the larger UN-sponsored global climate summit -- known as COP31 -- to be held in Turkey next month.

From Barron's ● Oct. 7, 2026

A quick survey of current diseases lets us trace out four stages in the evolution of a specialized human disease from an animal precursor.

From "Guns, Germs, and Steel: The Fates of Human Societies" by Jared M. Diamond

They were the first known victims of the Shahed-136 drone, whose precursors had only appeared in Iranian state media and 2019 strikes on Saudi oil facilities.

From The Wall Street Journal ● Aug. 26, 2026

Directed by Henry Winkler and co-starring Lee Majors as Mountain Dan, it may be one of the earliest precursors to the Hallmark holiday-style movies.

From Salon ● Aug. 26, 2026

The rover has found chemical traces left behind by this wetter period, including carbon-based molecules believed to be precursors to RNA and DNA, two nucleic acids that carry genetic information.

From Science Daily ● Aug. 1, 2026

“The use of the books at issue to train Claude and its precursors was exceedingly transformative and was a fair use,” Alsup noted in his earlier judgment.

From Los Angeles Times ● Jul. 23, 2026

In reality, even for the most famous and apparently decisive modern inventions, neglected precursors lurked behind the bald claim “X invented Y.”

From "Guns, Germs, and Steel: The Fates of Human Societies" by Jared M. Diamond

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Related Words

• forerunner
• harbinger

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