cleavage
//ˈkliːvɪdʒ//
Noun
The act or process of splitting or dividing something, especially along a natural line or plane.
The cleavage of the rock along its natural fault lines made it easier to extract.
A sharp division or split, especially between groups or opinions.
There is a deep cleavage between the two political parties on this issue.
The hollow between a woman's breasts, especially when made visible by a low-cut garment.
Her dress showed a lot of cleavage.
(Biology) The series of cell divisions by which a fertilized egg develops into a blastula.
Cleavage begins shortly after fertilization and results in the formation of a blastula.
(Geology/Mineralogy) The tendency of a crystalline substance to split along definite planes, yielding smooth surfaces.
Mica has perfect cleavage, which allows it to be split into thin sheets.