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: body part 
Words: inch, head, foot, ear, finger

SOLUTION: inch

PROBLEM: Category: animal 
Words: bird, flutter, jump, waggle, fly

SOLUTION: flutter

PROBLEM: Category: consumer product 
Words: ecstatic, specialty, substance, content, merchandise

SOLUTION:
ecstatic