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: angular momentum, fat, calcium, brittleness, ugly
Example Output: calcium

Example Input: pounce, car, bats, fly, grasshopper
Example Output: car

Example Input: eagle, flutter, fly, swim, train
Example Output:
eagle