Word Frequency Count Within a List

I'm wondering if it is possible to get the count of words within a list, not a table or file. This article shows a way to do it with a file: https://blog.crossjoin.co.uk/2013/03/15/finding-shakespeares-favourite-words-with-data-explorer/

However, I'll need to do it on several rows individually. Basically I'd be perforfing this on a column from a GroupBy calculation. So I need the counts according to each item that was grouped by.

Haven't had any luck finding an answer. I'd appreciate all help. Thanks in advance!