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

And that is what Moriarty and Hennepin County will test in this case, which, if it succeeds, could be a precursor to charges in other such incidents, including the killings of Pretti and Good.

From Slate • Apr. 17, 2026

Not much different than it was in 1792, when 24 brokers established the precursor to the New York Stock Exchange, selling shares of shipping and insurance concerns to the city’s leading citizens.

From Barron's • Apr. 15, 2026

But long before that, in 1871, inventor Antonio Meucci received a “caveat,” a precursor to a patent, for his version of a telephone, which he called a speaking telegraph.

From The Wall Street Journal • Apr. 12, 2026

In fact, stars have been taking cues from Hollywood history at precursor awards shows.

From Los Angeles Times • Mar. 15, 2026

That could have been the precursor to an independent African discovery of iron metallurgy.

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

Related Words

• forerunner
• harbinger