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.

Q: ounce, foot, kilometer, milimeter, heel

A: heel
****
Q: forward, opposite of up, unhappy, downward, down

A: unhappy
****
Q: brisk, loyal, decent, fair, honorable

A:
brisk
****