envelope
a tent? a block of cheese?
The Toblerone box is like a triangular prism; any ordinary box is like a rectangular prism.
A tent...
Toblerone (a Swiss chocolate)
A pencil
A cow's head is shaped sort of like a triangular prism, so that's probably what you would call it: a triangular prism.
Some things shaped like a triangular prism include certain types of buildings, such as pyramids or triangular roof structures. Certain crystals, like bipyramidal quartz, can also have a triangular prism shape. In geometry, a triangular prism itself is a solid shape with two triangular bases and three rectangular faces.
It will look like a cone-shaped party hat from the side and a bullseye from the top.
Prism-like and triangular.
glass prism, a 4-sided dice (i have 2)
A block of cheese,house roof,a ten,A paper boat