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: type of sandwich 
Words: hoagie, burger, hamburger, club, discothek
discothek

Category: boats 
Words: bridge, deck, stern, dock, suits
suits

Category: moral characteristic 
Words: fair, luke, equitable, alright, decent

luke