Weaire-Phelan structure

Etymology
Named after Denis Weaire and Robert Phelan, who in 1993 found that this structure was a better solution to the Kelvin problem of tiling space by equal-volume cells of minimum surface area than the previous best-known solution, the Kelvin structure.

Noun

 * 1)  A three-dimensional structure representing an idealized foam of equal-sized bubbles, with two different shapes.