Glade.
open space aswhiteen the blood vessels.
volumetric space is open, it isn't like a garden that has trees, planters, etc.. in the way, it is more like an open plaza. Piazza san Marco in Venice, Italy is a great example.
A Vault
vault
An open space within a building is typically referred to as an "atrium." An atrium is a large open area often located at the center of a building, providing natural light and ventilation. It is commonly used as a gathering space or for aesthetic purposes in architectural design.
A clearingAnswerAn open space surrounded by trees is called a glade
The tubular space within an artery is referred to as the lumen. It is the inner open space where blood flows.
An open space
glade
Porosity refers to the percentage of open space between individual rock particles in a rock layer. This space can be between grains or within the cracks or cavities of the rock.
A Glade or a Clearing
The ability of a subsurface rock to hold water is called porosity. Porosity refers to the volume of open space within a rock that can hold water, allowing it to flow and be stored within the rock matrix.
An open circuit is called open because the circuit has an opening, a disconnection. In other words, there is an open space in the circuit in which the electrons cannot move through.
I don't think there is a particular name for the area. It is just a passageway to allow people to walk abaft (behind) the bridge, it would be called a companionway. If it is larger, then is just open space or open deck area within the bridge deck.
This space was called a forum. If it were in Greece, it would have been called an agora.
It is usually called a landing.