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Related to Lamarckianism: catastrophism
La·marck·ism(lə-mär′kĭz′əm) also La·marck·i·an·ism (-kē-ə-nĭz′əm)
A theory of biological evolution holding that the changes occurring in an organism through use and disuse of its body parts in response to environmental change are inherited by its offspring.
[After Chevalier Jean Baptiste Pierre Antoine de Monet de Lamarck.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.