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: boxing terminology 
Words: apron, punch, deck, canvas, call
Example Output: call

Example Input: Category: bird 
Words: ostrich, digger, sandpiper, crane, goose
Example Output: digger

Example Input: Category: emotional display 
Words: colt, fawn, swoon, suppressed, social
Example Output:
colt