Why is a static method considered a method?

Question

I'm writing an explanation for some code for a course, and have been accidentally using the words method and function interchangeably. I decided to go back over and fix the wording, but ran into a hole in my understanding.

From what I understand, a subroutine is a function if it doesn't act on an instance of a class (its effect is restricted to its explicit input/output), and is a method if it operates on an instance of a class (it may carry out side effects on the instance that make it impure).

There's a good discussion here on the topic. Note that by the accepted answer's definitions, a static method should actually be a function because an instance is never implicitly passed, and it doesn't have access to any instance's members.

With this in mind though, shouldn't static methods actually be functions?

By their definition they don't act on particular instances of a class; they're only "tied" to the class because of relation. I've seen a few good looking sites that refer to static subroutines as "methods" though (Oracle, Fredosaurus, ProgrammingSimplified), so either they're all overlooking the terminology, or I'm missing something (my guess is the latter).

I'd like to make sure I am using the correct wording.
Can anybody clear this up?

Answer 1

This quote from 8.4.3.2 may help:

A method that is declared static is called a class method.

A method that is not declared static is called an instance method [...].

• Class methods: associated with a class.
• Instance methods: associated with an instance.

Java just wants you to "think object-oriented". Also, static methods have access to a surrounding scope which may include state. In a way, the class is like an object itself.