precursor

American  

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

noun

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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Etymology

Origin of precursor

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

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

Company executives have said it’s a precursor to broader institutional adoption of crypto and could unlock trillions of dollars in assets flowing into Bitcoin and other less-well-known tokens.

From Barron's • May 14, 2026

Another factor could be cabinet resignations, which as we saw with the previous Conservative government, can be a precursor to a prime minister being forced to stand down.

From BBC • May 10, 2026

Department of Homeland Security, a precursor to filing a federal civil rights lawsuit against the agency.

From Los Angeles Times • May 5, 2026

Spang solved this by processing the liquid precursor of the hydrogel in a centrifuge.

From Science Daily • May 5, 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

Related Words

• forerunner
• harbinger