| 1. | to interrogate (a soldier, astronaut, diplomat, etc.) on return from a mission in order to assess the conduct and results of the mission. |
| 2. | to question formally and systematically in order to obtain useful intelligence or information: Political and economic experts routinely debrief important defectors about conditions in their home country. |
| 3. | to subject to prohibitions against revealing or discussing classified information, as upon separation from a position of military or political sensitivity. |
| 4. | Psychology. (after an experiment) to disclose to the subject the purpose of the experiment and any reasons for deception or manipulation. |