A gate is an area in an airport terminal that controls access to a passenger aircraft.
A gate that provides access to multiple stands/jet bridges may have separate, designated doorways – sometimes termed sub-gates – for each stand.
Commercial airport stands have airside components to facilitate passenger boarding and aircraft ground handling.
[1]: 7-2 At most domestic gates, a single doorway connects the passenger waiting area with the jet bridge.
Before the era of the jet bridge or jetway, airline passengers embarked onto the aircraft from ground level via airstairs.