pe·nul·ti·mate / peˈnəltəmit/ • adj. last but one in a series of things; second to the last: the penultimate stage in the Tour. (you must pronounce it as Paul Sherwen does, try it again). Used in a sentence (when referring to the Tour de France): There are really only 20 stages, the race is over after the penultimate stage. Or: Let the champagne flow after the penultimate stage. Or: First there is the penultimate, then there is the ultimate.
As opposed to the Queen Stage (the hardest stage), or as we would say in American jargon The Mother of All Stages. Used in a sentence: What a Mother that was.