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.

[EX Q]: Category: guitar part 
Words: truss rod, fret, neck, bored, strap lock
[EX A]: bored

[EX Q]: Category: police punishment 
Words: flyaway, jail time, ok, arrest, fine
[EX A]: ok

[EX Q]: Category: accomodation 
Words: valley, paved, flat, round, mansion
[EX A]:
valley