What exactly is an "iterator"?

[timsong-cpp]

https://timsong-cpp.github.io/cppwp/iterator.requirements.general#3.sentence-2 defines it to mean "any type that models the Iterator concept".

But sometimes we use the word to mean the object rather than the type, e.g., https://timsong-cpp.github.io/cppwp/iterator.requirements.general#1.sentence-3

And sometimes we use the word to mean the "old" C++17 iterators rather than the new ones: https://timsong-cpp.github.io/cppwp/iterator.requirements#iterator.traits-1.sentence-2