Cleavage

n. splitting, rupturing; division, separation (between opinions, beliefs, etc.); area between a woman's breasts

Cleavage in general refers to a division or separation of form. Its usage is heavily dependent on cultural context, where it may refer to:Partial exposure of part of the body:Cleavage (breasts), partial exposure of the separation between a woman's breasts.Cleavage enhancement, methods of making a person's breast cleavage look better than it really is.Cleavage (buttocks), partial exposure of buttock cheeks, particularly when visible because of low trousers, also known colloquially in the UK as builder's bum and in the US as plumber's crack.Cleavage (belly), partial exposure of the skin between the chest and the waist. Cleavage (toes), partial exposure of the top of a woman's toes, particularly when visible because of shoes with low cut vamps.Cleavage (crystal), in mineralogy and materials science, is a process of splitting a single crystal.Cleavage (geology), Foliation perpendicular to stress as a result of ductile deformation. e.g. shales (shists) Cleavage (embryo), in embryology, is the division of cells in the early embryo. Cleavage (fiber), in optical fibers. Teeth cleavage or tooth cleavage, slang for Diastema (dentistry), the gap between a person's two front teeth. Cleavage (band), Toronto rock band.In cell biology, the Cleavage furrow is the indentation that begins the process of cleavage, by which animal cells undergo cytokinesis. Cleavage (chemistry and biochemistry) The breaking of chemical bonds. Cleavage (politics) The divisions of society that cause people to vote differently
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Noun
1. the state of being split or cleft
(hypernym) state
2. the breaking of a chemical bond in a molecule resulting in smaller molecules
(hypernym) chemical process, chemical change, chemical action
3. (embryology) the repeated division of a fertilised ovum
(synonym) segmentation
(hypernym) cell division, cellular division
(part-holonym) pregnancy, gestation, maternity
(classification) embryology
4. the line formed by a groove between two parts (especially the separation between a woman's breasts)
(hypernym) area, region
5. the act of cleaving or splitting
(hypernym) division
(derivation) cleave, split, rive

(n.)
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.
  

(n.)
The act of cleaving or splitting.
  

(n.)
Division into laminae, like slate, with the lamination not necessarily parallel to the plane of deposition; -- usually produced by pressure.
  

The tendency of certain minerals to break along distinct planes in their crystal structures where the bonds are weakest. Cleavage is tested by striking or hammering a mineral, and is classified by the number of surfaces it produces and the angles between adjacent surfaces.