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: bird 
Words: swift, tackle, pelican, crane, hoist
Example Output: hoist

Example Input: Category: aesthetic characteristic 
Words: high quality, ok, level, classy, fine
Example Output: ok

Example Input: Category: police punishment 
Words: classy, probation, custody, fine, flyaway
Example Output:
classy