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: below, backward, melancholy, down, ground
Example Output: melancholy

Example Input: Category: shady activities 
Words: fudge, banned, brownie, unwarranted, fib
Example Output: brownie

Example Input: Category: type of sandwich 
Words: doorstep, dance hall, club, lettuce, burger
Example Output:
dance hall