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: type of sandwich 
Words: grilled cheese, french toast, outing, burger, club
Example Output: outing

Example Input: Category: emotional status 
Words: truss rod, emotional supports, emotional upsets, emotionalities, fret
Example Output: truss rod

Example Input: Category: elements 
Words: fire, flame, burn, air, replace
Example Output:
replace