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: clothing, content, service, substance, ecstatic

A: ecstatic
****
Q: spring, run, fall, equinox, autumn

A: run
****
Q: spider, fly, train, jog, car

A:
spider
****