An extended arch is called a vault. Most tunnel are built using vaults. It's a bunch of arches put together.
An arch
The key stone is the stone placed at the apex of the arch, and prevents the two sides of the arch falling in and collapsing.
spandrel
VAULT
The "bullet" shape is called a Gothic arch. It is the evolution of the Romanesque arch which is just a semicircle, and has a number of structural advantages.
barrel vault
barrel vault
Semi Arch
The New Balance - 858 gives excellent arch support, it has an extended web along the TK for more support.
An arch in which the internal forces are purely axial is called a linear arch.
a foots palm is called the arch in your foot a foots palm is called the arch in your foot
The proscenium arch stage is so named due to the proscenium arch which separates the stage from the auditorium.
A extended episode.
The croquet arch is known as a hoop. The objects used to hit the balls in croquet are called mallets.
crown
coigne
An arch