javascript - What is .$ means for in CKEditor? -

i looking plugins of ckeditor. here code encountered:

var dummyelement = editor.document.createelement('span'); var obj = dummyelement.$; 

the plugin comes here.

what .$ means in context? supported in jquery or other libraries?

$ valid variable or property name without digging source code (or docs) , seeing assigned there no way know snippet alone used for

as seen here can it

var obj ={ $: 'foo'} alert(obj.$);// "foo"