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: elements 
Words: ground, replace, combustion, flame, fire
Example Output: replace

Example Input: Category: personal characteristic 
Words: assured, refreshing, unruffled, cool, positive
Example Output: refreshing

Example Input: Category: animal 
Words: spider, grasshopper, fly, dive, glide
Example Output:
glide