One of the solutions is to put a space at the beginning and end of the test word. This fails if the word is at the beginning or end of a sentence or is next to any punctuation. My solution is to write a function that replaces any punctuation in the test string with spaces, and add a space to the beginning and end or the test string and test word, then return the number of occurrences. This is a simple solution that removes the need for any complex regex expression.