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: activity 
Words: fritter, waste, pie, waste away, lollygag
Example Output: pie

Example Input: Category: bird 
Words: goose, hoist, neck, swallow, crane
Example Output: hoist

Example Input: Category: emotional status 
Words: alright, alert, fine, detached, level
Example Output:
level