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.

Example Input: Category: animal 
Words: train, fly, jump, leap, grasshopper
Example Output: train

Example Input: Category: body part 
Words: heel, shin, pound, finger, foot
Example Output: pound

Example Input: Category: activity 
Words: misuse, waste, fritter, pastry, goodbye
Example Output:
pastry