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: animal 
Words: flutter, swim, ant, fly, bats
Example Output: flutter

Example Input: Category: emotional status 
Words: nervous, frustrated, fret, jack, concerned
Example Output: jack

Example Input: Category: police punishment 
Words: probation, jail, arrest, fine, beautiful
Example Output:
beautiful