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: physical activity 
Words: sprint, get down, cow, duck, bow
Example Output: cow

Example Input: Category: shady activities 
Words: banned, replace, smear, chocolate cake, fudge
Example Output: chocolate cake

Example Input: Category: boxing terminology 
Words: deck, caution, jab, hull, fight
Example Output:
hull