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: chocolate food 
Words: rich, chocolate, fudge, chocolate cake, unwarranted
Example Output: unwarranted

Example Input: Category: mode of transportation 
Words: spider, fly, train, jog, car
Example Output: spider

Example Input: Category: emotional status 
Words: unhappy, disgusted, left, miserable, down
Example Output:
left