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noun pre·cur·sor \pri-ˈkər-sər, ˈprē-ˌ\

Simple Definition of precursor

  • : something that comes before something else and that often leads to or influences its development

Source: Merriam-Webster's Learner's Dictionary

Full Definition of precursor

  1. 1 a :  one that precedes and indicates the approach of another b :  predecessor

  2. 2 :  a substance, cell, or cellular component from which another substance, cell, or cellular component is formed


play \-ˈkərs-rē, -ˈkər-sə-\ adjective

Examples of precursor in a sentence

  1. <18th-century lyric poets like Robert Burns were precursors of the Romantics>

  2. <a precursor of the modern eggplant>

Did You Know?

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.

Origin and Etymology of precursor

Middle English precursoure, from Latin praecursor, from praecurrere to run before, from prae- pre- + currere to run — more at current

First Known Use: 15th century

Synonym Discussion of 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>.

Medical Dictionary


play play
noun pre·cur·sor \pri-ˈkər-sər, ˈprē-ˌ\

Medical Definition of precursor

  1. 1:  one that precedes and indicates the onset of another <angina may be the precursor of a second infarction>

  2. 2:  a substance, cell, or cellular component from which another substance, cell, or cellular component is formed especially by natural processes

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