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: jog, jump, fish, fly, bats
Example Output: jog

Example Input: Category: mode of transportation 
Words: spider, fly, train, jog, car
Example Output: spider

Example Input: Category: weather 
Words: make the grade, light, cold, fair, tangle
Example Output:
light