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

Example Input: fiber, big boned, protein, carbs, fat
Example Output: big boned

Example Input: neat, classy, fine, exquisite, penalty
Example Output:
penalty