Debriefing refers to a procedure conducted at the end of an experiment in which the researcher provides human participants with as much information about the study as possible, making sure no participant leaves feeling confused, upset, or embarrassed.

Other definition:
Debriefing refers to the the procedure whereby the purpose of the study and exactly what transpired is explained to participants at the end of an experiment

Other /More definition:
Debriefing is a term in Social psychology which refers to the post experimental explanation of a study to its participants. Usually, Debriefing discloses any deception and usually queries participants regarding their understandings and feelings; when subjects are told all details of an experiment after they have participated which is an ethical obligation of the researcher. Moreover, In research on human subjects, Debriefing is the legal requirement that researchers explain to participants the purpose, importance, and results of the research following their participation. Deception is the procedure whereby participants are misled about the true purpose of a study or the events that will actually transpire