1. The act of splitting or cleaving.
2. The state of being split or cleft; a fissure or division.
3. Mineralogy The splitting or tendency to split of a crystallized substance along definite crystalline planes, yielding smooth surfaces.
a. The series of mitotic cell divisions that produces a blastula from a fertilized ovum. It is the basis of the multicellularity of complex organisms. Also called segmentation.
b. Any single cell division in such a series.
5. Chemistry The splitting of a complex molecule, such as a polysaccharide, into simpler molecules.
6. Informal The cleft between a woman's breasts as revealed by a low-cut garment.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.