Thank you to everyone who answered my question. I humbly realize my theory is that of a naive midwestern cowtown misspent youth. I enjoyed the education about names and anatomy. Apparently my simple question about why the word "jack" appears so frequently in our language doesn't have an answer. And other languages do have the same types of occurrences of other words. listing all of the words that contain "Jack" was fun and we went on to list all the words we use for toilet and bathroom. I just saw a new show coming to CBS where all the characters are listing the alternative words to "scoundrel". Also I found Anu Garg's new book has a fun word game: spelling your name as well as names of other things backwards (stressed vs. desserts).