Definition
A secondary display page accessed from a main page on an electronic flight instrument or avionics unit, showing additional detail or related information that does not fit on the primary page.
Plain English
A page you open from another page on a cockpit screen to see more information.
Context Anchor
Seen when using aircraft displays that organize information into menus or pages, especially in glass-cockpit or flight management systems.
Derivation
From the prefix 'sub-' (Latin for 'under' or 'below') combined with 'page'. A subpage sits beneath a main page in the menu structure — you reach it by going down a level.
Why Pilots Care
Knowing how to navigate to and from subpages quickly matters in flight. Critical information like fuel planning, traffic, or approach data is often one or two subpages deep, and fumbling through menus while flying is both distracting and unsafe.
Intuition Check
A subpage is not a separate paper page. In this context, it means a secondary electronic screen reached from a main screen.
Example Sentence 1
He selected the flight plan subpage to review the next waypoint and estimated time en route.
Example Sentence 2
Each major section in the manual ends with a subpage listing related procedures.