cellular automaton

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A discrete mathematical model or dynamical system of an infinite, regular lattice in a finite number of dimensions, which consists of cells, each in a finite number of states. The cells evolve in discrete time steps according to a set of rules based on the state of both the cell and its neighboring cells.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun computing theory An automaton consisting of cells arranged in a regular grid, in one or more dimensions.