Is it correct to say function?

A "method" is a "function" that belongs to a class. Though "method" would be a more precise description either term is correct.

Keep in mind that a class method is defined using the keyword "function", e.g.

PHP Code:

<?php
class SimpleClass
{
    // method definition
    public function displayHello() {
        echo "Hello World";
    }
} 


Thank you so much!