The word ‘Dam’ is used for both the main barrier and for the totality of all structures that allow for flood control.
It’s worth remembering that dams are about flood control. That is their primary function. Water retention is a distant second.
If either spillway at Oroville were to fail, a hell of a lot of water would run downhill. That would be a classic dam failure, even if the main barrier remained intact.
True.