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: shady activities 
Words: falsification, fib, invent, fudge, cupcake
Example Output: cupcake

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

Example Input: Category: poker 
Words: hearts, deck, queen, suits, head
Example Output:
head