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: clothing, content, service, substance, ecstatic
Example Output: ecstatic

Example Input: townhome, mountain, studio, flat, apartment
Example Output: mountain

Example Input: courage, sausage, honest, harsh, frank
Example Output:
sausage