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: computers 
Words: image, format, reception, file, folder
Example Output: reception

Example Input: Category: physical property 
Words: fat, angular momentum, ugly, capacitance, fiber
Example Output: fiber

Example Input: Category: bird 
Words: windlass, hummingbird, neck, crane, duck
Example Output:
windlass