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: guitar part 
Words: neck, strap lock, fret, angry, notes
Example Output: angry

Example Input: Category: animal 
Words: hamster, fish, tiger, canyoning, sea turtle
Example Output: canyoning

Example Input: Category: personal characteristic 
Words: funny, cool, relaxed, tropical, calm
Example Output:
tropical