Definition of Eavesdropping
Eavesdropping is knowingly and without lawful authority: (a) Entering into a private place with intent to listen surreptitiously to private conversations or to observe the personal conduct of any other person or persons therein; or (b) Installing or using outside a private place any device for hearing, recording, amplifying, or broadcasting sounds originating in such place, which sounds would not ordinarily be audible or comprehensible outside, without the consent of the person or persons entitled to privacy therein; or (c) Installing or using any device or equipment for the interception of any telephone, telegraph or other wire communication without the consent of the person in possession or control of the facilities for such wire communication. Such activities are regulated by state and federal statutes, and commonly require a court order.
At common law, the offense of listening under walls or windows, or the eaves of a house, and thereupon to frame slanderous and mischievous tales. 4 Bl.Comm. 168. It was a misdemeanor at common law.
See also Pen register; Wiretapping.
That's the definition of Eavesdropping in Black's Law Dictionary 6th Edition. Courtesy of Cekhukum.com.