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: fish, bat, sea turtle, trap, goat
Example Output: trap

Example Input: Category: emotional status 
Words: well, detached, fine, wispy, relaxed
Example Output: wispy

Example Input: Category: emotional status 
Words: happy, disappointed, content, activity, ecstatic
Example Output:
activity