How to 'invert' an Xpath statement please

Hello all,

I'm new to this list.
This question might have been answerd before, nut please help me with the following question.

Please see the following example:
<ROOT>
    <ELEMENT>Element 1</ELEMENT>
    <NODE>
        <ELEMENT>Element 2</ELEMENT>
        <ELEMENT>Element 3</ELEMENT>
    </NODE>
</ROOT>

The normal xpath statement '//NODE' will give me:
NODE, ELEMENT (with Element 2), ELEMENT (With Element 3)

I'm experimenting with some inverted statements:
For instance: /*[!//NODE] or //*[!//NODE] 
It keeps giving me the NODE data as well.

The inverted selection *should* produce:
ROOT, ELEMENT (With Element 1)
Any advice on how to put the statement together?

(Information: In my program, the user will create the xpath statement, and than my program needs the inverted statement internaly)

Friendly greetings
Rens