That's outside the standard meaning of Alan Kay's term "dynamic binding," which originates in a different meaning of "binding", namely, "linking object files (into an executable or other form of memory image)". The Mesa linker, for example, was called the "binder". These conflicting meanings of "binding" make for a good pun or joke, but I think there are people trying to read this discussion in all seriousness to understand the linguistic issues, and the pun could confuse them.
It happens that in ordinary Lisps†, the function called by invoking a symbol does depend on the run-time value of a symbol (its function binding in a Lisp-2), and that's the sense in which an ordinary Scheme or (non-generic) Common Lisp function call can be said to be "dynamically bound", but that isn't the case in general. So even in that sense it doesn't correspond to the static/dynamic scoping distinction that they seem to be trying to discuss.
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† I think this may be one of the points where Lush is atypical; I think its interpreter supports runtime rebinding of the function bindings of symbols, but its compiler doesn't. I'm not sure, though. I may not have used Lush this millennium.
The Lisp term "dynamic" means "stack-like LIFO discipline".
"Dynamic scope" is a shorthand that refers to "indefinite scope with dynamic extent", where "dynamic extent" refers to the bindings being tied to stack-like frames, such that they are torn down then constructs terminate.
When we "declare dynamic-extent" an object, the compiler may stack-allocate it.
The C language redefined "dynamic" from "stack" to "heap". If you look into the BCPL manual (one predecessor language that inspired Ken Thompson's B), it uses "dynamic extent" to refer to the stack, which C renamed to "automatic storage":
"[T]he extent of a dynamic data item starts when its declaration is executed and continues until execution leaves the scope of the declaration." (1967 BCPL Manual, 7.2)
It happens that in ordinary Lisps†, the function called by invoking a symbol does depend on the run-time value of a symbol (its function binding in a Lisp-2), and that's the sense in which an ordinary Scheme or (non-generic) Common Lisp function call can be said to be "dynamically bound", but that isn't the case in general. So even in that sense it doesn't correspond to the static/dynamic scoping distinction that they seem to be trying to discuss.
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† I think this may be one of the points where Lush is atypical; I think its interpreter supports runtime rebinding of the function bindings of symbols, but its compiler doesn't. I'm not sure, though. I may not have used Lush this millennium.