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: direction 
Words: up, descending, down, lower, melancholy
Example Output: melancholy

Example Input: Category: physical property 
Words: bulky, skinny, carbs, absorption, fat
Example Output: carbs

Example Input: Category: weather 
Words: cold, loyal, fair, make the grade, brisk
Example Output:
loyal