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: mad, beautiful, comfortable, fine, relaxed
Example Output: beautiful

Example Input: glass, wood, coating, knifer, woodwork
Example Output: knifer

Example Input: spider, fly, bats, cockroach, bike
Example Output:
bike