Medical Dictionary
2 ENTRIES FOUND:

precursor

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

Definition of PRECURSOR

1
:  one that precedes and indicates the onset of another <angina may be the precursor of a second infarction>
2
:  a substance, cell, or cellular component from which another substance, cell, or cellular component is formed especially by natural processes
March 29, 2015
discomfit Hear it
To thwart or disconcert
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