A screw thread, often shortened to thread, is a helical structure used to convert between rotational and linear movement or force. A screw thread is a ridge wrapped around a cylinder or cone in the form of a helix, with the former being called a straight thread and the latter called a tapered thread. A screw thread is the essential feature of the screw as a simple machine and also as a fastener.
Quick Answer. Tin is an element that is made up of the mineral cassiterite and mined from the crust of the earth. The combination of cassiterite and carbon in a high heat setting forms the type of tin that is used in modern applications. Continue Reading.
atomic number 50, Sn. 1  tin foil, tinfoil - foil made of tin or an alloy of tin and lead. 2  metal, metallic element - any of several chemical elements that are usually shiny solids that conduct heat or electricity and can be formed into sheets etc. 3  cassiterite - a hard heavy dark mineral that is the chief source of tin.