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: streamline, sustainability, private, firm, stiff
Example Output: stiff

Example Input: medium, unjust, flaxen, fair, texture
Example Output: unjust

Example Input: sunny, fair, make the grade, equitable, raining
Example Output:
equitable