A vehicle (usually a bus, coach or train) or aircraft with two floors.
Any object with two layers or parts stacked on top of each other.
A sandwich with three slices of bread, whose toppings are on both sides of the middle slice.
A headline that is two lines long.
a man who both penetrates (top) and is penetrated (bottom) in sex with other men; sometimes also has relationships with women and/or presents masculine as well as feminine mannerisms and appearances.
A frigate with two decks above the waterline.
the rooms housing such equipment
any equipment that establishes connections between telephones