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: date status 
Words: current, delayed, postponed, brine, late
brine

Category: aesthetic characteristic 
Words: high quality, ok, level, classy, fine
ok

Category: window material 
Words: metal, panel, wood, glass, knife

knife