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, notes, emotional upsets, output cord, truss rod
emotional upsets

Category: physical property 
Words: sugars, fat, thin, large, angular momentum
sugars

Category: outdoor sport activity 
Words: fish, iguana, kayak, trap, raft

iguana