Given a set of five words, generate the word from the set that does not belong (i.e. is the least relevant) with the other words. Words are separated by commas.

Example Input: fair, even, milky, ghostly, luke
Example Output: luke

Example Input: fat, ugly, sugar, salt, protein
Example Output: ugly

Example Input: fawn, follow, expression, colt, paw
Example Output:
colt