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hopeful monster

American  

noun

Biology.

  1. a hypothetical individual organism that, by means of a fortuitous macromutation permitting an adaptive shift to a new mode of life, becomes the founder of a new type of organism and a vehicle of macroevolution.

Etymology

Origin of hopeful monster

First recorded in 1933; phrase introduced by German geneticist Richard B. Goldschmidt (1879–1958)

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.