Plain English Meaning
A piece of airspace you are not allowed to fly into at all. Entry is forbidden by regulation, not just discouraged.
Full Definition
A block of airspace, designated by regulation, within which the flight of aircraft is forbidden. Prohibited Areas are established for reasons of national security or other essential interest, and are depicted on aeronautical charts with defined lateral and vertical limits.
Context Anchor
Seen on aeronautical charts and during route planning, especially near places protected for security or national welfare.
Derivation
“Prohibited” comes from a Latin word meaning “to hold back” or “to prevent.” That fits the aviation meaning: this is airspace where aircraft are held back from entering unless .