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: personal characteristic 
Words: cold, positive, calm, assured, cool
Example Output: cold

Example Input: Category: weather 
Words: cold, luke, fair, mild, light
Example Output: light

Example Input: Category: physical property 
Words: pasty, vitamin c, chunky, angular momentum, fat
Example Output:
vitamin c