Given a set of five words, generate the word from the set that does not belong (i.e. is the least relevant) with the other words. Words are separated by commas.

Example Input: order office supplies, file, errands, prepare, motherboard
Example Output: motherboard

Example Input: squashed, cabin, flat, smooth, round
Example Output: smooth

Example Input: kayak, trap, horse, fish, hike
Example Output:
horse