Cell cleavage

Cleavage Cleav"age, n. 1. The act of cleaving or splitting. [1913 Webster]

2. (Crystallog.) 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}. [1913 Webster]

3. (Geol.) Division into lamin[ae], like slate, with the lamination not necessarily parallel to the plane of deposition; -- usually produced by pressure. [1913 Webster]

{Basal cleavage}, cleavage parallel to the base of a crystal, or to the plane of the lateral axes.

{Cell cleavage} (Biol.), multiplication of cells by fission. See {Segmentation}.

{Cubic cleavage}, cleavage parallel to the faces of a cube.

{Diagonal cleavage}, cleavage parallel to ta diagonal plane.

{Egg clavage}. (Biol.) See {Segmentation}.

{Lateral cleavage}, cleavage parallel to the lateral planes.

{Octahedral cleavage}, {Dodecahedral cleavage}, or {Rhombohedral cleavage}, cleavage parallel to the faces of an octahedron, dodecahedron, or rhombohedron.

{Prismatic cleavage}, cleavage parallel to a vertical prism. [1913 Webster]