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: construction 
Words: excavator, steam roller, concrete pourer, swallow, crane
Example Output: swallow

Example Input: Category: chocolate food 
Words: brownie, loosen, chocolate cake, fudge, molasses
Example Output: loosen

Example Input: Category: aesthetic characteristic 
Words: fair, color, trustworthy, well, flaxen
Example Output:
trustworthy