I want to fetch last word dynamically

Hi All ,

I want to fetch the last word from the short description and store in the one of the variable :

var gr= current.short_description;

var words = s.trim().split(gr);
var lengthOfLastWord = words[words.length - 1];
gs.print(lengthOfLastWord); 

var ab=lengthOfLastWord;

This script is not fetching the last word .Can anyone help me .

Thanks and Regards,

Chandan