The term bellows is used by extension for a flexible bag whose volume can be changed by compression or expansion, but not used to deliver air. For example, the light-tight (but not airtight) bag allowing the distance between the lens and film of a folding photographic camera to be varied is called a bellows.
What NFL has lost the Super Bowl the most? The Buffalo Bills, the Denver Broncos, the Minnesota Vikings, and the New England Patriots have all lost four Super Bowls. Edit
The Detroit Lions, Cleveland Browns (current iteration), Jacksonville Jaguars, and Houston Texans are the only current teams to have never played in a Super Bowl. Detroit did play in NFL Championships prior to the establishment of the Super Bowl in the 1966-67 season, as did the original Cleveland Browns. The latter two are expansion teams (as is the new iteration of the Browns) so they don't have as many years of history to work with. Cleveland is weird because the original Cleveland Browns team that became the Ravens never played in a Super Bowl during their time in Cleveland, but did play (and win) as the Ravens.