Given a category and a set of five words, find the word from the set that does not belong (i.e. is the least relevant) with the other words in the category. Words are separated by commas.

Category: emotional status 
Words: concerned, board, nervous, emotional, fret
board

Category: elements 
Words: fire, retire, ice, air, earth
retire

Category: weather 
Words: deal, 70, equitable, fair, raining

equitable