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: physical property 
Words: obese, fat, vitamin c, heavy, thin
Example Output: vitamin c

Example Input: Category: aesthetic characteristic 
Words: high quality, ok, level, classy, fine
Example Output: ok

Example Input: Category: outdoor sport activity 
Words: climbing, hunt, fish, canyoning, hamster
Example Output:
hamster