1. The process of becoming mature.
a. The processes by which gametes are formed, including the reduction of chromosomes in a germ cell from the diploid number to the haploid number by meiosis.
b. The final differentiation processes in biological systems, such as the final ripening of a seed or the attainment of full functional capacity by a cell, a tissue, or an organ.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 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.