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: fly, grasshopper, walk, waggle, train
Example Output: train

Example Input: tide, belated, signal, current, jetstream
Example Output: belated

Example Input: raining, sunny, endure, tone, fair
Example Output:
tone