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: corporate 
Words: unyielding, concerted, firm, combined, united
unyielding

Category: aesthetic characteristic 
Words: level, fair, milky, sunny, well
sunny

Category: emotional status 
Words: well, detached, decent, fine, level

level