jQuery plugin's syntax is too strange

jQuery plugin's syntax is too strange

I have a little trouble about the meaning of syntax "(function( $ )" and
"(jQuery)" in the below code.
(function( $ ){
$.fn.myPlugin = function() {
// Do your awesome plugin stuff here
};})(jQuery);
Can you please explain what meaning of them ?
If I want to change phrase "(jQuery)" in the above code to "(abc)" then
how to do it and how to use it ?
Thanks for taking the time to answer my question.