orthogenesis

noun

or·​tho·​gen·​e·​sis ˌȯr-thə-ˈje-nə-səs 

: variation of organisms in successive generations that in some especially former evolutionary theories takes place in some predestined direction resulting in progressive evolutionary trends independent of external factors

orthogenetic

ˌȯr-thə-jə-ˈne-tik 

adjective

orthogenetically

ˌȯr-thə-jə-ˈne-ti-k(ə-)lē 

adverb

Examples of orthogenesis in a Sentence

Recent Examples on the Web

Sperm structure and motility in the eusocial naked mole-rat, Heterocephalus glaber: a case of degenerative orthogenesis in the absence of sperm competition? —Ed Yong, Discover Magazine, 4 Dec. 2011

The various models proposed for the mechanism of evolution, such as Lamarckian evolution, orthogenesis and use-disuse, all implied some level of teleology: that there was a directionality inherent in the process. —Mano Singham, Scientific American, 5 Sep. 2021

The various models proposed for the mechanism of evolution, such as Lamarckian evolution, orthogenesis, and use-disuse, all implied some level of teleology, that there was a directionality inherent in the process. —Mano Singham, Scientific American, 5 Sep. 2021

Word History

Etymology

New Latin

First Known Use

1895, in the meaning defined above

Medical Definition

orthogenesis

noun

or·​tho·​gen·​e·​sis ˌȯr-thə-ˈjen-ə-səs 

plural orthogeneses -ˌsēz 

: variation of organisms in successive generations that in some evolutionary theories takes place in some predestined direction and results in progressive evolutionary trends independent of external factors

orthogenetic

-jə-ˈnet-ik 

adjective