Plain English Meaning
The picture-language a flight display uses — the shapes and markings that show the pilot what the aircraft is doing and what is around it.
Full Definition
The set of standardized symbols, icons, and graphical elements used on a cockpit display to represent aircraft attitude, flight path, terrain, traffic, navigation references, and other flight information.
Context Anchor
Seen in discussions of Synthetic Vision Guidance Systems, flight displays, and other cockpit screens that show guidance using visual marks instead of only words or numbers.
Derivation
From Greek 'symbolon' meaning 'sign' or 'token,' combined with '-logy' meaning 'study or system of.' So 'symbology' literally means 'a system of symbols' — in , the visual language used on a display.