TASK DEFINITION: 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.
PROBLEM: Category: boxing terminology 
Words: caution, hearts, canvas, deck, fight

SOLUTION: hearts

PROBLEM: Category: type of sandwich 
Words: picnic, open-faced, club, grilled cheese, lettuce

SOLUTION: picnic

PROBLEM: Category: type of rigidity 
Words: firm, rough, inflexible, rigged, combined

SOLUTION:
combined