Given a category and a set of five words, find the word from the set that does not belong (i.e. is the least relevant) with the other words in the category. Words are separated by commas.

Example Input: Category: outdoor sport activity 
Words: fish, hiking, row, shark, canoe
Example Output: shark

Example Input: Category: outdoor sport activity 
Words: hunt, row, wrestle, fish, hamster
Example Output: hamster

Example Input: Category: construction 
Words: ostrich, tackle, digger, crane, windlass
Example Output:
ostrich