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: guitar part 
Words: fret, worried, chord, notes, headstock
worried

Category: social gathering 
Words: grilled cheese, place, club, dance hall, meeting
grilled cheese

Category: guitar part 
Words: emotional supports, fret, truss rod, notes, output cord

emotional supports