Definition - What does Espionage mean?
Espionage refers to a crime against federal government. This usually involves spying on the government on behalf of some other country and transporting sensitive information into that country. Espionage can also be treated as treason if the country is an enemy of the state.
Justipedia explains Espionage
Espionage usually forms an integral part of intelligence activities. This includes act of collecting sensitive industrial, military, and political information of one country that can be analyzed by another country for its benefits.