Noun

(en noun)

The act of cleaving or the state of being cleft.

(mineralogy) The tendency of a crystal to split along specific planes.

(biology) The repeated division of a cell into daughter cells after mitosis.

The hollow or separation between a woman's breasts, especially as revealed by a low neckline.

* 1946 , "Cinema: Cleavage and the Code", Time , 5 Aug 1946:

Low-cut Restoration costumes worn by the Misses Lockwood and Roc (see cut) display too much "cleavage " (Johnston Office trade term for the shadowed depression dividing an actress' bosom into two distinct sections).

(chemistry) The splitting of a large molecule into smaller ones.

(politics) The division of voters into voting blocs.

Noun

(en noun)

(geology) A linear feature in rock, often structural

magnetic lineations

(literature) The way in which line breaks are inserted in a poem

*{{quote-book, 2001, Shira Wolosky, The Art of Poetry citation

, passage=Lineation is very much a matter of syntax, organizing the poem's grammar across its lines in ways significant and central to the poem's meaning.}}