In
geometry, a **slab** is a region between two
parallel lines in the
Euclidean plane,^{
[1]} or between two parallel
planes in three-dimensional Euclidean space or between two
hyperplanes in
higher dimensions.^{
[2]}

A slab can also be defined as a set of points:^{
[3]}

where is the normal vector of the planes and .

Or, if the slab is centered around the origin:^{
[4]}

where is the thickness of the slab.

**^**Preparata, Franco P.; Shamos, Michael Ian (1985). "2.2.2.1 The slab method".*Computational Geometry: An Introduction*. New York: Springer. pp. 45–48. doi: 10.1007/978-1-4612-1098-6. ISBN 978-1-4612-7010-2. S2CID 206656565.**^**Jacob, Goodman. "Handbook of Discrete and Computational Geometry". CRC Press LLC. Retrieved 24 July 2022.**^**S., Boyd. "Convex Optimization". Cambridge University Press. Retrieved 14 March 2022.**^**Jean-Luc, Marichal; Mossinghoff, Michael J. (2008). "Slices, slabs, and sections of the unit hypercube" (PDF).*Online Journal of Analytic Combinatorics*.**3**(1). arXiv: math/0607715.