This name is given to the private person upon whose complaint or information a criminal accusation is founded and whose testimony is mainly relied on to secure a conviction at the trial; in a more particular sense, the person who was chiefly injured, in person or property, by the act constituting the alleged crime, (as in cases of robbery, assault, criminal negligence , battery, and the like,) and who instigates the prosecution and gives evidence.
Black’s Law Online Dictionary
