instruction:
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.
question:
Category: measurement unit 
Words: meter, inch, foot, heel, pound
answer:
heel


question:
Category: guitar part 
Words: truss rod, fret, neck, bored, strap lock
answer:
bored


question:
Category: physical activity 
Words: jog, cow, hike, duck, crouch
answer:

cow