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: type of rigidity 
Words: tough, taut, rough, amalgamated, firm
answer:
amalgamated


question:
Category: animal 
Words: dangle, fly, run, car, pounce
answer:
car


question:
Category: boxing terminology 
Words: corner, box, punch, deck, check
answer:

check