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: mode of transportation 
Words: dive, fly, soar, jog, wave
Example Output: dive

Example Input: Category: bird 
Words: dump truck, pelican, goose, crane, derrick
Example Output: dump truck

Example Input: Category: boats 
Words: bow, gunwale, crew, deck, blocking
Example Output:
blocking