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: construction 
Words: windlass, crane, dump truck, pelican, digger
pelican

Category: emotional status 
Words: emotional, ground, ashamed, emotional upsets, down
ground

Category: aesthetic characteristic 
Words: mad, level, fine, hot, exquisite

mad