The portion of a surface left when an open disk is removed from it.

# Perforation

## See also

Open Disk## Explore with Wolfram|Alpha

## References

Francis, G. K. and Weeks, J. R. "Conway's ZIP Proof."*Amer. Math. Monthly*

**106**, 393-399, 1999.

## Referenced on Wolfram|Alpha

Perforation## Cite this as:

Weisstein, Eric W. "Perforation." From
*MathWorld*--A Wolfram Web Resource. https://mathworld.wolfram.com/Perforation.html