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: ocean 
Words: signal, timely, brine, flow, current
Example Output: timely

Example Input: Category: outdoor sport activity 
Words: hike, cow, trap, row, fish
Example Output: cow

Example Input: Category: secretary duty 
Words: organize, file, errands, reception, space
Example Output:
space