[ awr-thuh-jen-uh-sis ]
/ ˌɔr θəˈdʒɛn ə sɪs /


  1. Also called orthoselection. evolution of a species proceeding by continuous structural changes in a single lineage without presenting a branching pattern of descent.
  2. a theory that the evolution of a species in a continuous, nonbranching manner is due to a predetermined series of alterations intrinsic to the species and not subject to natural selection.
Sociology. a hypothetical parallelism between the stages through which every culture necessarily passes, in spite of secondary conditioning factors.

Origin of orthogenesis

From New Latin, dating back to 1890–95; see origin at ortho-, genesis
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for orthogenesis

  • Eimer, of Germany, has based on facts like these his theory of Orthogenesis.

    The Meaning of Evolution|Samuel Christian Schmucker
  • This theory of Orthogenesis has not figured very strongly in the history of the movement, but it recurs at intervals.

    The Meaning of Evolution|Samuel Christian Schmucker
  • What is the third objection to Darwinism, and what is the bearing upon it of the theory of Orthogenesis?

    The Meaning of Evolution|Samuel Christian Schmucker
  • The same can be said of any one of the teological theories, including the orthogenesis of post-Darwinian writers.

    American Weasels|E. Raymond Hall

British Dictionary definitions for orthogenesis


/ (ˌɔːθəʊˈdʒɛnɪsɪs) /


  1. evolution of a group of organisms predetermined to occur in a particular direction
  2. the theory that proposes such a development
the theory that there is a series of stages through which all cultures pass in the same order

Derived Forms

orthogenetic (ˌɔːθəʊdʒɪˈnɛtɪk), adjectiveorthogenetically, adverb
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012