Plain English Meaning
Talked through after the flight to go over how it went and what to learn from it.
Full Definition
Reviewed in a structured discussion after a flight or training event, during which the instructor and pilot examine what happened, what went well, what did not, and what should be done differently next time.
Context Anchor
Seen in flight training, aircraft checkouts, transition training, and instructor sign-off discussions after a flight or lesson.
Derivation
From 'de-' (reverse or undo) plus 'brief' (a short set of instructions given before an event). A pre-flight briefing sets up what will happen; a debriefing unpacks what actually did happen afterward.
Why Pilots Care
Systematic debriefing turns raw flight experience into faster learning and safer habits.