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

Math is “changing certainly quite dramatically” because of AI, Jayawardhana said, calling it “a precursor to what’s coming to other fields.”

From Los Angeles Times ● Oct. 29, 2026

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

Experiments using mouse precursor fat cells supported this idea.

From Science Daily ● Oct. 24, 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

Unfortunately, the colony losses from 2006 to 2020 were a precursor to a much larger crisis to come, which ultimately resulted in the Global Famine of 2100.

From "The First State of Being" by Erin Entrada Kelly

"Using this method, we have directly converted red blood cell precursors into neural stem cells," explains Prof. Dr. Oliver Brüstle, director of the Institute of Reconstructive Neurobiology at the University Hospital of Bonn.

From Science Daily ● Oct. 21, 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 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

The White House document claimed they had discussed Chinese investment in U.S. industries, purchases of U.S. oil and agricultural products, and ending the flow of fentanyl precursors into the U.S.

From Slate ● May 16, 2026

From a patent lawyer’s perspective, the ideal invention is one that arises without any precursors, like Athene springing fully formed from the forehead of Zeus.

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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