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.

Category: direction 
Words: up, down, sliding, shameful, right
shameful

Category: boats 
Words: head, hull, knockout, deck, dock
knockout

Category: animal 
Words: bee, fish, spider, jog, fly

jog