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: boxing terminology 
Words: deck, gunwale, level, tko, jab
Example Output: gunwale

Example Input: Category: emotional status 
Words: fret, truss rod, emotional upsets, sad, worried
Example Output: truss rod

Example Input: Category: consumer product 
Words: content, food, ecstatic, item, jewelry
Example Output:
ecstatic