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: ecstatic, content, disappointed, sad, service
Example Output: service

Example Input: mallet, goose, geese, hike, duck
Example Output: hike

Example Input: high quality, fine, jail, custody, flyaway
Example Output:
high quality