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: animal 
Words: swim, dive, fly, car, bee
car

Category: aesthetic characteristic 
Words: fair, medium, size, light, loyal
loyal

Category: boats 
Words: bridge, lifeline, crew, deck, canvas

canvas