The term 'spy plant' refers to a type of espionage technique in which a person is placed in an organization or country to gather information. The term can also refer to the use of plants to conceal listening devices or cameras. In this crossword, the solution for the term 'spy plant' is 'MOLE, ' which is a person who works undercover to obtain information. A MOLE is typically someone who is trusted by the organization or country they are infiltrating and is able to gain access to sensitive information.