Word Study
lamarckism
CIDE DICTIONARY
lamarckism, n. [From Lamarck, a distinguished French naturalist.].
The theory that structural variations, characteristic of species and genera, are produced in animals and plants by the direct influence of physical environments, and esp., in the case of animals, by effort, or by use or disuse of certain organs. It is a discredited theory, not believed by modern biologists. [1913 Webster]
OXFORD DICTIONARY
lamarckism, n. the theory of evolution devised by Lamarck, French botanist and zoologist (d. 1829), based on the inheritance of acquired characteristics.
Derivative
Lamarckian n. & adj.
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