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: poker 
Words: board, joker, deck, fold, apron

SOLUTION: apron

PROBLEM: Category: guitar part 
Words: neck, fret, jack, pick, angry

SOLUTION: angry

PROBLEM: Category: measurement unit 
Words: head, ounce, foot, centimeter, milimeter

SOLUTION:
head