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: close, nearest, touching, on top of, barred
Example Output: barred

Example Input: glass, acrylic, wood, metal, plate
Example Output: plate

Example Input: classy, fine, neat, hot, mad
Example Output:
mad