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: corporate 
Words: unyielding, concerted, firm, combined, united
Example Output: unyielding

Example Input: Category: consumer product 
Words: shop, tools, happy, service, content
Example Output: happy

Example Input: Category: aesthetic characteristic 
Words: sunny, medium, flaxen, fair, even
Example Output:
sunny