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: poker 
Words: fold, deck, board, call, knockout
Example Output: knockout

Example Input: Category: police punishment 
Words: wispy, fine, probation, calm, prime
Example Output: calm

Example Input: Category: boxing terminology 
Words: lifeline, canvas, corner, ring, deck
Example Output:
lifeline