thermocoagulation 1. The process of converting tissue into a gel by heat. 2. Coagulation of tissue by the action of high-frequency currents; used in removal of growths and also used to produce stereotactic lesions in the brain. 3. Destruction and removal of tissue by coagulation utilizing high-frequency electric current. Found on http://www.wordinfo.info/words/index/info/view_unit/512/