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: measurement unit 
Words: meter, inch, foot, heel, pound
Example Output: heel

Example Input: Category: boxing terminology 
Words: canvas, tko, deck, joker, fight
Example Output: joker

Example Input: Category: aesthetic characteristic 
Words: beautiful, fine, there, annoyed, bright
Example Output:
annoyed