Black's Law Dictionary (2nd edition)dictionaries

Prosecuting Witness

This name is given to the private person upon whose complaint or information a criminal accusa-tion is founded and whose testimony is maln-ly relied on to secure a conviction at the trial; in a more particular sense, the person who was chiefly injured, in person or prop-erty, by the act constituting the alleged crime, (as in cases of robbery, assault, criminal negligence, bastardy, aud tbe liked and who instigates the prosecution and gives evi-ddnce

Source: Black's Law Dictionary 2nd Ed (1910)