cleavage

noun

cleav·​age ˈklē-vij 

1

a

: the quality of a crystallized substance or rock of splitting along definite planes

also : the occurrence of such splitting

b

: a fragment (as of a diamond) obtained by splitting

2

: the action of cleaving or splitting : the state of being cleft

3

: the series of synchronized mitotic cell divisions of a fertilized egg that results in the formation of the blastomeres and changes the single-celled zygote into a multicellular embryo

also : one of these cell divisions

4

: the splitting of a molecule into simpler molecules

5

: the depression between a woman's breasts especially when made visible by a low-cut neckline

Synonyms of cleavage

• split
• dissolution
• breakup
• partition
• division
• separation

Examples of cleavage in a Sentence

The dress is cut low enough to reveal a lot of cleavage.

the cleavage between the rich and poor

the cleavages of an egg as an embryo develops

Recent Examples on the Web

Epstein in a mud mask or his toes in Ghislaine Maxwell's cleavage might be unsettling, but is hardly what former deputy FBI director Dan Bongino once claimed would be revealed when the first dump of Epstein files dropped. —Eve Batey, Vanity Fair, 17 Jan. 2026

And, yes, the rumors are true - the first cut was rated R by the MPAA, and the female stars' cleavage was CGI'd away so as not to offend. —Raechal Shewfelt, Entertainment Weekly, 16 Jan. 2026

The Instagram post includes pictures of Nichole with a bruised lip, leg and arm and scratches on her face, shoulder and cleavage. —Rebecca Tauber, New York Times, 8 Jan. 2026

Through a precise alpha-cleavage pathway, the catalyst guides glucose so that eighty percent of the molecules are successfully converted into high-value formate. —Aman Tripathi, Interesting Engineering, 4 Jan. 2026

Word History

First Known Use

1816, in the meaning defined at sense 1a

Phrases Containing cleavage

• discoidal cleavage
• radial cleavage
• spiral cleavage

Kids Definition

cleavage

noun

cleav·​age ˈklē-vij 

1

: the quality of a crystallized substance or rock of splitting in definite directions

2

: the action of cleaving : the state of being cleaved

3

: the series of mitotic cell divisions of a fertilized egg that changes the single cell into a many-celled embryo

Medical Definition

cleavage

noun

cleav·​age ˈklē-vij 

1

: the series of synchronized mitotic cell divisions of the fertilized egg that results in the formation of the blastomeres and changes the single-celled zygote into a multicellular embryo

also : one of these cell divisions

2

: the splitting of a molecule into simpler molecules