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: swallow, heron, crane, flamingo, tackle
Example Output: tackle

Example Input: mild, cold, level, stormy, fair
Example Output: level

Example Input: wispy, fine, probation, calm, prime
Example Output:
calm