a print made by an impression of the ridges in the skin of a finger; often used for biometric identification in criminal investigations

Plural form of investigation

The act of investigating; the process of inquiring into or following up; research; study; inquiry, especially patient or thorough inquiry or examination; as, the investigations of the philosopher and the mathematician; the investigations of the judge, the moralist, an inquiry into unfamiliar or questionable activities, the work of inquiring into something thoroughly and systematically