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: secretary duty 
Words: support, hardware, prepare, file, make coffee
Example Output: hardware

Example Input: Category: mode of transportation 
Words: spider, fly, train, jog, car
Example Output: spider

Example Input: Category: moral characteristic 
Words: just, trustworthy, unjust, fair, milky
Example Output:
milky