lattice
subgroup of a real vector space
face-centered cubic
one of two densest possible sphere packings in 3D Euclidean space
reciprocal lattice
fourier transform of real-space lattices, important in solid-state physics
hexagonal close packing
one of two densest possible sphere packings in 3D Euclidean space
Hexagonal lattice
one of the five 2D Bravais lattices