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: poker 
Words: level, blind, pack, draw, deck
level

Category: type of rigidity 
Words: rigged, firm, unyielding, streamline, taut
streamline

Category: bird 
Words: steam roller, duck, crane, egret, pelican

steam roller