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: bird 
Words: ostrich, digger, sandpiper, crane, goose
Example Output: digger

Example Input: Category: animal 
Words: fish, iguana, canyoning, hamster, horse
Example Output: canyoning

Example Input: Category: boats 
Words: deck, rudder, sail, canvas, gunwale
Example Output:
canvas