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: weather 
Words: brisk, ghostly, windy, fair, deal
ghostly

Category: window material 
Words: glass, coating, panel, spatula, lead
spatula

Category: weather 
Words: medium, fair, endure, clime, windy

medium