Definition
Automatically removes non-essential symbols, data, and information from a cockpit display so that only the information needed for the current task or flight situation remains visible.
Plain English
Hides extra stuff on the screen so you can see what matters right now.
Context Anchor
Seen in descriptions of electronic flight displays and unusual attitude recovery protection, where the screen may simplify itself during recovery.
Derivation
From 'clutter' (a disordered heap or mess) with the prefix 'de-' meaning 'remove' or 'undo.' To de-clutter is literally to take the mess away. The aviation use applies this directly to a screen full of symbols.
Why Pilots Care
Prevents information overload that could delay recognition and recovery from an unusual attitude.
Intuition Check
Do not read de-clutters as the system fixing the airplane or removing information from the aircraft. It means the display shows less on the screen so the important cues stand out.
Example Sentence 1
When the aircraft entered an unusual attitude, the PFD automatically de-clutters, leaving only the attitude indicator and basic flight references visible.
Example Sentence 2
The pilot can manually command the display to de-clutter during a high-workload approach.