3 Terms and definitions [intro.defs]

3.9 dynamic type [defns.dynamic.type]

⟨glvalue⟩ type of the most derived object ([intro.object]) to which the glvalue refers
[Example
:
If a pointer ([dcl.ptr]) p whose static type is “pointer to class B” is pointing to an object of class D, derived from B (Clause [class.derived]), the dynamic type of the expression *p is “D.
References ([dcl.ref]) are treated similarly.
end example
]