Cleavage

·noun The act of cleaving or splitting.

II. Cleavage ·noun Division into laminae, like slate, with the lamination not necessarily parallel to the plane of deposition;

— usually produced by pressure.

III. Cleavage ·noun The quality possessed by many crystallized substances of splitting readily in one or more definite directions, in which the cohesive attraction is a minimum, affording more or less smooth surfaces; the direction of the dividing plane; a fragment obtained by cleaving, as of a diamond. ·see Parting.