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: ubiquitous, captain, typical, general, boring
Example Output: captain

Example Input: shark, hiking, hike, wrestle, fish
Example Output:
shark