The definition of a precursor is something or someone that came before.
(noun)An example of a precursor is the dark clouds before a storm.
Precursor is defined as something that led to the creation of something similar but new.
(noun)An example of precursor is how radio came before but helped create television.
See precursor in Webster's New World College Dictionary
noun
Origin: L praecursor < praecurrere, to run ahead: see pre- & current
See precursor in American Heritage Dictionary 4
noun
Origin:
Origin: Middle English precursoure
Origin: , from Old French precurseur
Origin: , from Latin praecursor
Origin: , from praecursus
Origin: , past participle of praecurrere, to run before
Origin: : prae-, pre-
Origin: + currere, to run; see kers- in Indo-European roots
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