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: swallow, heron, crane, flamingo, tackle
Example Output: tackle

Example Input: duplex, studio, cabin, horizontal, flat
Example Output: horizontal

Example Input: swim, fly, bird, spider, dangle
Example Output:
swim